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1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd">
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2 <HTML
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3 ><HEAD
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4 ><TITLE
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5 >LW Tool Chain</TITLE
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6 ><META
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7 NAME="GENERATOR"
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8 CONTENT="Modular DocBook HTML Stylesheet Version 1.79"></HEAD
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9 ><BODY
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10 CLASS="BOOK"
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11 BGCOLOR="#FFFFFF"
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12 TEXT="#000000"
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13 LINK="#0000FF"
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14 VLINK="#840084"
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15 ALINK="#0000FF"
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16 ><DIV
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17 CLASS="BOOK"
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18 ><A
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19 NAME="AEN1"
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20 ></A
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21 ><DIV
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22 CLASS="TITLEPAGE"
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23 ><H1
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24 CLASS="TITLE"
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25 ><A
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26 NAME="AEN2"
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27 >LW Tool Chain</A
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28 ></H1
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29 ><H3
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30 CLASS="AUTHOR"
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31 ><A
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32 NAME="AEN4"
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33 ></A
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34 >William Astle</H3
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35 ><P
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36 CLASS="COPYRIGHT"
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37 >Copyright © 2009 William Astle</P
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38 ><HR></DIV
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39 ><DIV
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40 CLASS="TOC"
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41 ><DL
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42 ><DT
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43 ><B
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44 >Table of Contents</B
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45 ></DT
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46 ><DT
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47 >1. <A
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48 HREF="#AEN10"
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49 >Introduction</A
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50 ></DT
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51 ><DD
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52 ><DL
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53 ><DT
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54 >1.1. <A
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55 HREF="#AEN13"
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56 >History</A
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57 ></DT
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58 ></DL
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59 ></DD
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60 ><DT
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61 >2. <A
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62 HREF="#AEN18"
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63 >Output Formats</A
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64 ></DT
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65 ><DD
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66 ><DL
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67 ><DT
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68 >2.1. <A
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69 HREF="#AEN21"
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70 >Raw Binaries</A
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71 ></DT
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72 ><DT
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73 >2.2. <A
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74 HREF="#AEN24"
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75 >DECB Binaries</A
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76 ></DT
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77 ><DT
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78 >2.3. <A
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79 HREF="#AEN29"
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80 >Object Files</A
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81 ></DT
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82 ></DL
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83 ></DD
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84 ><DT
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85 >3. <A
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86 HREF="#AEN35"
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87 >LWASM</A
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88 ></DT
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89 ><DD
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90 ><DL
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91 ><DT
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92 >3.1. <A
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93 HREF="#AEN38"
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94 >Command Line Options</A
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95 ></DT
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96 ><DT
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97 >3.2. <A
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98 HREF="#AEN121"
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99 >Dialects</A
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100 ></DT
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101 ><DT
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102 >3.3. <A
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103 HREF="#AEN126"
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104 >Source Format</A
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105 ></DT
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106 ><DT
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107 >3.4. <A
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108 HREF="#AEN135"
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109 >Symbols</A
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110 ></DT
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111 ><DT
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112 >3.5. <A
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113 HREF="#AEN139"
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114 >Numbers and Expressions</A
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115 ></DT
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116 ><DT
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117 >3.6. <A
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118 HREF="#AEN146"
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119 >Assembler Directives</A
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120 ></DT
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121 ><DD
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122 ><DL
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123 ><DT
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124 >3.6.1. <A
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125 HREF="#AEN149"
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126 >Data Directives</A
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127 ></DT
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128 ><DT
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129 >3.6.2. <A
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130 HREF="#AEN243"
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131 >Address Definition</A
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132 ></DT
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133 ><DT
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134 >3.6.3. <A
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135 HREF="#AEN285"
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136 >Conditional Assembly</A
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137 ></DT
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138 ><DT
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139 >3.6.4. <A
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140 HREF="#AEN349"
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141 >Miscelaneous Directives</A
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142 ></DT
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143 ></DL
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144 ></DD
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145 ><DT
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146 >3.7. <A
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147 HREF="#AEN378"
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148 >Macros</A
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149 ></DT
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150 ><DT
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151 >3.8. <A
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152 HREF="#AEN400"
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153 >Object Files and Sections</A
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154 ></DT
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155 ><DT
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156 >3.9. <A
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157 HREF="#AEN458"
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158 >Assembler Modes and Pragmas</A
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159 ></DT
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160 ></DL
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161 ></DD
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162 ><DT
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163 >4. <A
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164 HREF="#AEN491"
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165 >LWLINK</A
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166 ></DT
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167 ><DD
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168 ><DL
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169 ><DT
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170 >4.1. <A
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171 HREF="#AEN494"
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172 >Command Line Options</A
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173 ></DT
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174 ><DT
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175 >4.2. <A
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176 HREF="#AEN591"
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177 >Linker Operation</A
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178 ></DT
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179 ><DT
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180 >4.3. <A
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181 HREF="#AEN605"
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182 >Linking Scripts</A
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183 ></DT
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184 ></DL
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185 ></DD
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186 ><DT
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187 >5. <A
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188 HREF="#AEN639"
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189 >Libraries and LWAR</A
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190 ></DT
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191 ><DD
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192 ><DL
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193 ><DT
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194 >5.1. <A
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195 HREF="#AEN643"
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196 >Command Line Options</A
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197 ></DT
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198 ></DL
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199 ></DD
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200 ><DT
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201 >6. <A
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202 HREF="#OBJCHAP"
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203 >Object Files</A
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204 ></DT
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205 ></DL
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206 ></DIV
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207 ><DIV
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208 CLASS="LOT"
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209 ><DL
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210 CLASS="LOT"
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211 ><DT
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212 ><B
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213 >List of Tables</B
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214 ></DT
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215 ><DT
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216 >6-1. <A
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217 HREF="#AEN726"
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218 >Object File Term Types</A
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219 ></DT
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220 ><DT
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221 >6-2. <A
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222 HREF="#AEN753"
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223 >Object File Operator Numbers</A
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224 ></DT
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225 ></DL
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226 ></DIV
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227 ><DIV
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228 CLASS="CHAPTER"
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229 ><HR><H1
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230 ><A
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231 NAME="AEN10"
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232 ></A
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233 >Chapter 1. Introduction</H1
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234 ><P
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235 >The LW tool chain provides utilities for building binaries for MC6809 and
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236 HD6309 CPUs. The tool chain includes a cross-assembler and a cross-linker
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237 which support several styles of output.</P
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238 ><DIV
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239 CLASS="SECTION"
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240 ><HR><H2
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241 CLASS="SECTION"
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242 ><A
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243 NAME="AEN13"
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244 >1.1. History</A
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245 ></H2
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246 ><P
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247 >For a long time, I have had an interest in creating an operating system for
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248 the Coco3. I finally started working on that project around the beginning of
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249 2006. I had a number of assemblers I could choose from. Eventually, I settled
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250 on one and started tinkering. After a while, I realized that assembler was not
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251 going to be sufficient due to lack of macros and issues with forward references.
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252 Then I tried another which handled forward references correctly but still did
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253 not support macros. I looked around at other assemblers and they all lacked
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254 one feature or another that I really wanted for creating my operating system.</P
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255 ><P
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256 >The solution seemed clear at that point. I am a fair programmer so I figured
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257 I could write an assembler that would do everything I wanted an assembler to
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258 do. Thus the LWASM probject was born. After more than two years of on and off
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259 work, version 1.0 of LWASM was released in October of 2008.</P
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260 ><P
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261 >As the aforementioned operating system project progressed further, it became
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262 clear that while assembling the whole project through a single file was doable,
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263 it was not practical. When I found myself playing some fancy games with macros
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264 in a bid to simulate sections, I realized I needed a means of assembling
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265 source files separately and linking them later. This spawned a major development
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266 effort to add an object file support to LWASM. It also spawned the LWLINK
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267 project to provide a means to actually link the files.</P
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268 ></DIV
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269 ></DIV
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270 ><DIV
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271 CLASS="CHAPTER"
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272 ><HR><H1
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273 ><A
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274 NAME="AEN18"
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275 ></A
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276 >Chapter 2. Output Formats</H1
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277 ><P
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278 >The LW tool chain supports multiple output formats. Each format has its
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279 advantages and disadvantages. Each format is described below.</P
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280 ><DIV
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281 CLASS="SECTION"
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282 ><HR><H2
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283 CLASS="SECTION"
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284 ><A
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285 NAME="AEN21"
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286 >2.1. Raw Binaries</A
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287 ></H2
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288 ><P
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289 >A raw binary is simply a string of bytes. There are no headers or other
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290 niceties. Both LWLINK and LWASM support generating raw binaries. ORG directives
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291 in the source code only serve to set the addresses that will be used for
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292 symbols but otherwise have no direct impact on the resulting binary.</P
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293 ></DIV
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294 ><DIV
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295 CLASS="SECTION"
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296 ><HR><H2
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297 CLASS="SECTION"
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298 ><A
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299 NAME="AEN24"
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300 >2.2. DECB Binaries</A
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301 ></H2
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302 ><P
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303 >A DECB binary is compatible with the LOADM command in Disk Extended
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304 Color Basic on the CoCo. They are also compatible with CLOADM from Extended
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305 Color Basic. These binaries include the load address of the binary as well
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306 as encoding an execution address. These binaries may contain multiple loadable
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307 sections, each of which has its own load address.</P
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308 ><P
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309 >Each binary starts with a preamble. Each preamble is five bytes long. The
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310 first byte is zero. The next two bytes specify the number of bytes to load
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311 and the last two bytes specify the address to load the bytes at. Then, a
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312 string of bytes follows. After this string of bytes, there may be another
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313 preamble or a postamble. A postamble is also five bytes in length. The first
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314 byte of the postamble is $FF, the next two are zero, and the last two are
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315 the execution address for the binary.</P
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316 ><P
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317 >Both LWASM and LWLINK can output this format.</P
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318 ></DIV
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319 ><DIV
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320 CLASS="SECTION"
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321 ><HR><H2
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322 CLASS="SECTION"
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323 ><A
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324 NAME="AEN29"
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325 >2.3. Object Files</A
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326 ></H2
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327 ><P
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328 >LWASM supports generating a proprietary object file format which is
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329 described in <A
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330 HREF="#OBJCHAP"
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331 >Chapter 6</A
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332 >. LWLINK is then used to link these
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333 object files into a final binary in any of LWLINK's supported binary
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334 formats.</P
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335 ><P
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336 >Object files are very flexible in that they allow references that are not
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337 known at assembly time to be resolved at link time. However, because the
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338 addresses of such references are not known, there is no way for the assembler
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339 has to use sixteen bit addressing modes for these references. The linker
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340 will always use sixteen bits when resolving a reference which means any
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341 instruction that requires an eight bit operand cannot use external references.</P
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342 ><P
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343 >Object files also support the concept of sections which are not valid
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344 for other output types. This allows related code from each object file
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345 linked to be collapsed together in the final binary.</P
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346 ></DIV
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347 ></DIV
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348 ><DIV
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349 CLASS="CHAPTER"
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350 ><HR><H1
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351 ><A
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352 NAME="AEN35"
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353 ></A
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354 >Chapter 3. LWASM</H1
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355 ><P
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356 >The LWTOOLS assembler is called LWASM. This chapter documents the various
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357 features of the assembler. It is not, however, a tutorial on 6x09 assembly
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358 language programming.</P
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359 ><DIV
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360 CLASS="SECTION"
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361 ><HR><H2
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362 CLASS="SECTION"
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363 ><A
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364 NAME="AEN38"
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365 >3.1. Command Line Options</A
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366 ></H2
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367 ><P
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368 >The binary for LWASM is called "lwasm". Note that the binary is in lower
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369 case. lwasm takes the following command line arguments.</P
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370 ><P
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371 ></P
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372 ><DIV
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373 CLASS="VARIABLELIST"
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374 ><DL
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375 ><DT
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376 ><CODE
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377 CLASS="OPTION"
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378 >--decb</CODE
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379 >, <CODE
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380 CLASS="OPTION"
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381 >-b</CODE
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382 ></DT
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383 ><DD
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384 ><P
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385 >Select the DECB output format target. Equivalent to <CODE
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386 CLASS="OPTION"
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387 >--format=decb</CODE
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388 >.</P
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389 ></DD
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390 ><DT
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391 ><CODE
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392 CLASS="OPTION"
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393 >--format=type</CODE
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394 >, <CODE
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395 CLASS="OPTION"
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396 >-f type</CODE
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397 ></DT
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398 ><DD
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399 ><P
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400 >Select the output format. Valid values are <CODE
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401 CLASS="OPTION"
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402 >obj</CODE
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403 > for the object
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404 file target, <CODE
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405 CLASS="OPTION"
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406 >decb</CODE
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407 > for the DECB LOADM format, and <CODE
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408 CLASS="OPTION"
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409 >raw</CODE
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410 >
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411 for a raw binary.</P
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412 ></DD
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413 ><DT
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414 ><CODE
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415 CLASS="OPTION"
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416 >--list[=file]</CODE
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417 >, <CODE
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418 CLASS="OPTION"
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419 >-l[file]</CODE
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420 ></DT
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421 ><DD
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422 ><P
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423 >Cause LWASM to generate a listing. If <CODE
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424 CLASS="OPTION"
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425 >file</CODE
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426 > is specified,
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427 the listing will go to that file. Otherwise it will go to the standard output
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428 stream. By default, no listing is generated.</P
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429 ></DD
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430 ><DT
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431 ><CODE
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432 CLASS="OPTION"
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433 >--obj</CODE
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434 ></DT
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435 ><DD
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436 ><P
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437 >Select the proprietary object file format as the output target.</P
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438 ></DD
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439 ><DT
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440 ><CODE
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441 CLASS="OPTION"
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442 >--output=FILE</CODE
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443 >, <CODE
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444 CLASS="OPTION"
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445 >-o FILE</CODE
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446 ></DT
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447 ><DD
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448 ><P
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449 >This option specifies the name of the output file. If not specified, the
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450 default is <CODE
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451 CLASS="OPTION"
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|
|
452 >a.out</CODE
|
|
|
453 >.</P
|
|
|
454 ></DD
|
|
|
455 ><DT
|
|
|
456 ><CODE
|
|
|
457 CLASS="OPTION"
|
|
|
458 >--pragma=pragma</CODE
|
|
|
459 >, <CODE
|
|
|
460 CLASS="OPTION"
|
|
|
461 >-p pragma</CODE
|
|
|
462 ></DT
|
|
|
463 ><DD
|
|
|
464 ><P
|
|
|
465 >Specify assembler pragmas. Multiple pragmas are separated by commas. The
|
|
|
466 pragmas accepted are the same as for the PRAGMA assembler directive described
|
|
|
467 below.</P
|
|
|
468 ></DD
|
|
|
469 ><DT
|
|
|
470 ><CODE
|
|
|
471 CLASS="OPTION"
|
|
|
472 >--raw</CODE
|
|
|
473 >, <CODE
|
|
|
474 CLASS="OPTION"
|
|
|
475 >-r</CODE
|
|
|
476 ></DT
|
|
|
477 ><DD
|
|
|
478 ><P
|
|
|
479 >Select raw binary as the output target.</P
|
|
|
480 ></DD
|
|
|
481 ><DT
|
|
|
482 ><CODE
|
|
|
483 CLASS="OPTION"
|
|
|
484 >--help</CODE
|
|
|
485 >, <CODE
|
|
|
486 CLASS="OPTION"
|
|
|
487 >-?</CODE
|
|
|
488 ></DT
|
|
|
489 ><DD
|
|
|
490 ><P
|
|
|
491 >Present a help screen describing the command line options.</P
|
|
|
492 ></DD
|
|
|
493 ><DT
|
|
|
494 ><CODE
|
|
|
495 CLASS="OPTION"
|
|
|
496 >--usage</CODE
|
|
|
497 ></DT
|
|
|
498 ><DD
|
|
|
499 ><P
|
|
|
500 >Provide a summary of the command line options.</P
|
|
|
501 ></DD
|
|
|
502 ><DT
|
|
|
503 ><CODE
|
|
|
504 CLASS="OPTION"
|
|
|
505 >--version</CODE
|
|
|
506 >, <CODE
|
|
|
507 CLASS="OPTION"
|
|
|
508 >-V</CODE
|
|
|
509 ></DT
|
|
|
510 ><DD
|
|
|
511 ><P
|
|
|
512 >Display the software version.</P
|
|
|
513 ></DD
|
|
|
514 ><DT
|
|
|
515 ><CODE
|
|
|
516 CLASS="OPTION"
|
|
|
517 >--debug</CODE
|
|
|
518 >, <CODE
|
|
|
519 CLASS="OPTION"
|
|
|
520 >-d</CODE
|
|
|
521 ></DT
|
|
|
522 ><DD
|
|
|
523 ><P
|
|
|
524 >Increase the debugging level. Only really useful to people hacking on the
|
|
|
525 LWASM source code itself.</P
|
|
|
526 ></DD
|
|
|
527 ></DL
|
|
|
528 ></DIV
|
|
|
529 ></DIV
|
|
|
530 ><DIV
|
|
|
531 CLASS="SECTION"
|
|
|
532 ><HR><H2
|
|
|
533 CLASS="SECTION"
|
|
|
534 ><A
|
|
|
535 NAME="AEN121"
|
|
|
536 >3.2. Dialects</A
|
|
|
537 ></H2
|
|
|
538 ><P
|
|
|
539 >LWASM supports all documented MC6809 instructions as defined by Motorola.
|
|
|
540 It also supports all known HD6309 instructions. There is some variation,
|
|
|
541 however, in the pneumonics used for the block transfer instructions. LWASM
|
|
|
542 uses TFM for all four of them as do several other assemblers. Others, such
|
|
|
543 as CCASM, use four separate opcodes for it (compare: copy+, copy-, implode,
|
|
|
544 and explode). There are advantages to both methods. However, it seems like
|
|
|
545 TFM has the most traction and thus, this is what LWASM supports. Support
|
|
|
546 for such variations may be added in the future.</P
|
|
|
547 ><P
|
|
|
548 >The standard addressing mode specifiers are supported. These are the
|
|
|
549 hash sign ("#") for immediate mode, the less than sign ("<") for forced
|
|
|
550 eight bit modes, and the greater than sign (">") for forced sixteen bit modes.</P
|
|
|
551 ><P
|
|
|
552 >Additionally, LWASM supports using the asterisk ("*") to indicate
|
|
|
553 base page addressing. This should not be used in hand-written source code,
|
|
|
554 however, because it is non-standard and may or may not be present in future
|
|
|
555 versions of LWASM.</P
|
|
|
556 ></DIV
|
|
|
557 ><DIV
|
|
|
558 CLASS="SECTION"
|
|
|
559 ><HR><H2
|
|
|
560 CLASS="SECTION"
|
|
|
561 ><A
|
|
|
562 NAME="AEN126"
|
|
|
563 >3.3. Source Format</A
|
|
|
564 ></H2
|
|
|
565 ><P
|
|
|
566 >LWASM accepts plain text files in a relatively free form. It can handle
|
|
|
567 lines terminated with CR, LF, CRLF, or LFCR which means it should be able
|
|
|
568 to assemble files on any platform on which it compiles.</P
|
|
|
569 ><P
|
|
|
570 >Each line may start with a symbol. If a symbol is present, there must not
|
|
|
571 be any whitespace preceding it. It is legal for a line to contain nothing
|
|
|
572 but a symbol.</P
|
|
|
573 ><P
|
|
|
574 >The op code is separated from the symbol by whitespace. If there is
|
|
|
575 no symbol, there must be at least one white space character preceding it.
|
|
|
576 If applicable, the operand follows separated by whitespace. Following the
|
|
|
577 opcode and operand is an optional comment.</P
|
|
|
578 ><P
|
|
|
579 >A comment can also be introduced with a * or a ;. The comment character is
|
|
|
580 optional for end of statement comments. However, if a symbol is the only
|
|
|
581 thing present on the line other than the comment, the comment character is
|
|
|
582 mandatory to prevent the assembler from interpreting the comment as an opcode.</P
|
|
|
583 ><P
|
|
|
584 >For compatibility with the output generated by some C preprocessors, LWASM
|
|
|
585 will also ignore lines that begin with a #. This should not be used as a general
|
|
|
586 comment character, however.</P
|
|
|
587 ><P
|
|
|
588 >The opcode is not treated case sensitively. Neither are register names in
|
|
|
589 the operand fields. Symbols, however, are case sensitive.</P
|
|
|
590 ><P
|
|
|
591 >LWASM does not support line numbers in the file.</P
|
|
|
592 ></DIV
|
|
|
593 ><DIV
|
|
|
594 CLASS="SECTION"
|
|
|
595 ><HR><H2
|
|
|
596 CLASS="SECTION"
|
|
|
597 ><A
|
|
|
598 NAME="AEN135"
|
|
|
599 >3.4. Symbols</A
|
|
|
600 ></H2
|
|
|
601 ><P
|
|
|
602 >Symbols have no length restriction. They may contain letters, numbers, dots,
|
|
|
603 dollar signs, and underscores. They must start with a letter, dot, or
|
|
|
604 underscore.</P
|
|
|
605 ><P
|
|
|
606 >LWASM also supports the concept of a local symbol. A local symbol is one
|
|
|
607 which contains either a "?" or a "@", which can appear anywhere in the symbol.
|
|
|
608 The scope of a local symbol is determined by a number of factors. First,
|
|
|
609 each included file gets its own local symbol scope. A blank line will also
|
|
|
610 be considered a local scope barrier. Macros each have their own local symbol
|
|
|
611 scope as well (which has a side effect that you cannot use a local symbol
|
|
|
612 as an argument to a macro). There are other factors as well. In general,
|
|
|
613 a local symbol is restricted to the block of code it is defined within.</P
|
|
|
614 ></DIV
|
|
|
615 ><DIV
|
|
|
616 CLASS="SECTION"
|
|
|
617 ><HR><H2
|
|
|
618 CLASS="SECTION"
|
|
|
619 ><A
|
|
|
620 NAME="AEN139"
|
|
|
621 >3.5. Numbers and Expressions</A
|
|
|
622 ></H2
|
|
|
623 ><P
|
|
|
624 > Numbers can be expressed in binary, octal, decimal, or hexadecimal. Binary
|
|
|
625 numbers may be prefixed with a "%" symbol or suffixed with a "b" or "B".
|
|
|
626 Octal numbers may be prefixed with "@" or suffixed with "Q", "q", "O", or
|
|
|
627 "o". Hexadecimal numbers may be prefixed with "$", "0x" or "0X", or suffixed
|
|
|
628 with "H". No prefix or suffix is required for decimal numbers but they can
|
|
|
629 be prefixed with "&" if desired. Any constant which begins with a letter
|
|
|
630 must be expressed with the correct prefix base identifier or be prefixed
|
|
|
631 with a 0. Thus hexadecimal FF would have to be written either 0FFH or $FF.
|
|
|
632 Numbers are not case sensitive. </P
|
|
|
633 ><P
|
|
|
634 > A symbol may appear at any point where a number is acceptable. The
|
|
|
635 special symbol "*" can be used to represent the starting address of the
|
|
|
636 current source line within expressions. </P
|
|
|
637 ><P
|
|
|
638 >The ASCII value of a character can be included by prefixing it with a
|
|
|
639 single quote ('). The ASCII values of two characters can be included by
|
|
|
640 prefixing the characters with a quote (").</P
|
|
|
641 ><P
|
|
|
642 >LWASM supports the following basic binary operators: +, -, *, /, and %.
|
|
|
643 These represent addition, subtraction, multiplication, division, and modulus.
|
|
|
644 It also supports unary negation and unary 1's complement (- and ^ respectively).
|
|
|
645 For completeness, a unary positive (+) is supported though it is a no-op.</P
|
|
|
646 ><P
|
|
|
647 >Operator precedence follows the usual rules. multiplication, division,
|
|
|
648 and modulus take precedence over addition and subtraction. Unary operators
|
|
|
649 take precedence over binary operators. To force a specific order of evaluation,
|
|
|
650 parentheses can be used in the usual manner.</P
|
|
|
651 ></DIV
|
|
|
652 ><DIV
|
|
|
653 CLASS="SECTION"
|
|
|
654 ><HR><H2
|
|
|
655 CLASS="SECTION"
|
|
|
656 ><A
|
|
|
657 NAME="AEN146"
|
|
|
658 >3.6. Assembler Directives</A
|
|
|
659 ></H2
|
|
|
660 ><P
|
|
|
661 >Various directives can be used to control the behaviour of the
|
|
|
662 assembler or to include non-code/data in the resulting output. Those directives
|
|
|
663 that are not described in detail in other sections of this document are
|
|
|
664 described below.</P
|
|
|
665 ><DIV
|
|
|
666 CLASS="SECTION"
|
|
|
667 ><HR><H3
|
|
|
668 CLASS="SECTION"
|
|
|
669 ><A
|
|
|
670 NAME="AEN149"
|
|
|
671 >3.6.1. Data Directives</A
|
|
|
672 ></H3
|
|
|
673 ><P
|
|
|
674 ></P
|
|
|
675 ><DIV
|
|
|
676 CLASS="VARIABLELIST"
|
|
|
677 ><DL
|
|
|
678 ><DT
|
|
|
679 >FCB <CODE
|
|
|
680 CLASS="PARAMETER"
|
|
|
681 >expr[,...]</CODE
|
|
|
682 >, .DB <CODE
|
|
|
683 CLASS="PARAMETER"
|
|
|
684 >expr[,...]</CODE
|
|
|
685 >, .BYTE <CODE
|
|
|
686 CLASS="PARAMETER"
|
|
|
687 >expr[,...]</CODE
|
|
|
688 ></DT
|
|
|
689 ><DD
|
|
|
690 ><P
|
|
|
691 >Include one or more constant bytes (separated by commas) in the output.</P
|
|
|
692 ></DD
|
|
|
693 ><DT
|
|
|
694 >FDB <CODE
|
|
|
695 CLASS="PARAMETER"
|
|
|
696 >expr[,...]</CODE
|
|
|
697 >, .DW <CODE
|
|
|
698 CLASS="PARAMETER"
|
|
|
699 >expr[,...]</CODE
|
|
|
700 >, .WORD <CODE
|
|
|
701 CLASS="PARAMETER"
|
|
|
702 >expr[,...]</CODE
|
|
|
703 ></DT
|
|
|
704 ><DD
|
|
|
705 ><P
|
|
|
706 >Include one or more words (separated by commas) in the output.</P
|
|
|
707 ></DD
|
|
|
708 ><DT
|
|
|
709 >FQB <CODE
|
|
|
710 CLASS="PARAMETER"
|
|
|
711 >expr[,...]</CODE
|
|
|
712 >, .QUAD <CODE
|
|
|
713 CLASS="PARAMETER"
|
|
|
714 >expr[,...]</CODE
|
|
|
715 >, .4BYTE <CODE
|
|
|
716 CLASS="PARAMETER"
|
|
|
717 >expr[,...]</CODE
|
|
|
718 ></DT
|
|
|
719 ><DD
|
|
|
720 ><P
|
|
|
721 >Include one or more double words (separated by commas) in the output.</P
|
|
|
722 ></DD
|
|
|
723 ><DT
|
|
|
724 >FCC <CODE
|
|
|
725 CLASS="PARAMETER"
|
|
|
726 >string</CODE
|
|
|
727 >, .ASCII <CODE
|
|
|
728 CLASS="PARAMETER"
|
|
|
729 >string</CODE
|
|
|
730 >, .STR <CODE
|
|
|
731 CLASS="PARAMETER"
|
|
|
732 >string</CODE
|
|
|
733 ></DT
|
|
|
734 ><DD
|
|
|
735 ><P
|
|
|
736 >Include a string of text in the output. The first character of the operand
|
|
|
737 is the delimiter which must appear as the last character and cannot appear
|
|
|
738 within the string. The string is included with no modifications></P
|
|
|
739 ></DD
|
|
|
740 ><DT
|
|
|
741 >FCN <CODE
|
|
|
742 CLASS="PARAMETER"
|
|
|
743 >string</CODE
|
|
|
744 >, .ASCIZ <CODE
|
|
|
745 CLASS="PARAMETER"
|
|
|
746 >string</CODE
|
|
|
747 >, .STRZ <CODE
|
|
|
748 CLASS="PARAMETER"
|
|
|
749 >string</CODE
|
|
|
750 ></DT
|
|
|
751 ><DD
|
|
|
752 ><P
|
|
|
753 >Include a NUL terminated string of text in the output. The first character of
|
|
|
754 the operand is the delimiter which must appear as the last character and
|
|
|
755 cannot appear within the string. A NUL byte is automatically appended to
|
|
|
756 the string.</P
|
|
|
757 ></DD
|
|
|
758 ><DT
|
|
|
759 >FCS <CODE
|
|
|
760 CLASS="PARAMETER"
|
|
|
761 >string</CODE
|
|
|
762 >, .ASCIS <CODE
|
|
|
763 CLASS="PARAMETER"
|
|
|
764 >string</CODE
|
|
|
765 >, .STRS <CODE
|
|
|
766 CLASS="PARAMETER"
|
|
|
767 >string</CODE
|
|
|
768 ></DT
|
|
|
769 ><DD
|
|
|
770 ><P
|
|
|
771 >Include a string of text in the output with bit 7 of the final byte set. The
|
|
|
772 first character of the operand is the delimiter which must appear as the last
|
|
|
773 character and cannot appear within the string.</P
|
|
|
774 ></DD
|
|
|
775 ><DT
|
|
|
776 >ZMB <CODE
|
|
|
777 CLASS="PARAMETER"
|
|
|
778 >expr</CODE
|
|
|
779 ></DT
|
|
|
780 ><DD
|
|
|
781 ><P
|
|
|
782 >Include a number of NUL bytes in the output. The number must be fully resolvable
|
|
|
783 during pass 1 of assembly so no forward or external references are permitted.</P
|
|
|
784 ></DD
|
|
|
785 ><DT
|
|
|
786 >ZMD <CODE
|
|
|
787 CLASS="PARAMETER"
|
|
|
788 >expr</CODE
|
|
|
789 ></DT
|
|
|
790 ><DD
|
|
|
791 ><P
|
|
|
792 >Include a number of zero words in the output. The number must be fully
|
|
|
793 resolvable during pass 1 of assembly so no forward or external references are
|
|
|
794 permitted.</P
|
|
|
795 ></DD
|
|
|
796 ><DT
|
|
|
797 >ZMQ <CODE
|
|
|
798 CLASS="PARAMETER"
|
|
|
799 >expr<CODE
|
|
|
800 CLASS="PARAMETER"
|
|
|
801 ></CODE
|
|
|
802 ></CODE
|
|
|
803 ></DT
|
|
|
804 ><DD
|
|
|
805 ><P
|
|
|
806 >Include a number of zero double-words in the output. The number must be fully
|
|
|
807 resolvable during pass 1 of assembly so no forward or external references are
|
|
|
808 permitted.</P
|
|
|
809 ></DD
|
|
|
810 ><DT
|
|
|
811 >RMB <CODE
|
|
|
812 CLASS="PARAMETER"
|
|
|
813 >expr</CODE
|
|
|
814 >, .BLKB <CODE
|
|
|
815 CLASS="PARAMETER"
|
|
|
816 >expr</CODE
|
|
|
817 >, .DS <CODE
|
|
|
818 CLASS="PARAMETER"
|
|
|
819 >expr</CODE
|
|
|
820 >, .RS <CODE
|
|
|
821 CLASS="PARAMETER"
|
|
|
822 >expr</CODE
|
|
|
823 ></DT
|
|
|
824 ><DD
|
|
|
825 ><P
|
|
|
826 >Reserve a number of bytes in the output. The number must be fully resolvable
|
|
|
827 during pass 1 of assembly so no forward or external references are permitted.
|
|
|
828 The value of the bytes is undefined.</P
|
|
|
829 ></DD
|
|
|
830 ><DT
|
|
|
831 >RMD <CODE
|
|
|
832 CLASS="PARAMETER"
|
|
|
833 >expr</CODE
|
|
|
834 ></DT
|
|
|
835 ><DD
|
|
|
836 ><P
|
|
|
837 >Reserve a number of words in the output. The number must be fully
|
|
|
838 resolvable during pass 1 of assembly so no forward or external references are
|
|
|
839 permitted. The value of the words is undefined.</P
|
|
|
840 ></DD
|
|
|
841 ><DT
|
|
|
842 >RMQ <CODE
|
|
|
843 CLASS="PARAMETER"
|
|
|
844 >expr</CODE
|
|
|
845 ></DT
|
|
|
846 ><DD
|
|
|
847 ><P
|
|
|
848 >Reserve a number of double-words in the output. The number must be fully
|
|
|
849 resolvable during pass 1 of assembly so no forward or external references are
|
|
|
850 permitted. The value of the double-words is undefined.</P
|
|
|
851 ></DD
|
|
|
852 ></DL
|
|
|
853 ></DIV
|
|
|
854 ></DIV
|
|
|
855 ><DIV
|
|
|
856 CLASS="SECTION"
|
|
|
857 ><HR><H3
|
|
|
858 CLASS="SECTION"
|
|
|
859 ><A
|
|
|
860 NAME="AEN243"
|
|
|
861 >3.6.2. Address Definition</A
|
|
|
862 ></H3
|
|
|
863 ><P
|
|
|
864 >The directives in this section all control the addresses of symbols
|
|
|
865 or the assembly process itself.</P
|
|
|
866 ><P
|
|
|
867 ></P
|
|
|
868 ><DIV
|
|
|
869 CLASS="VARIABLELIST"
|
|
|
870 ><DL
|
|
|
871 ><DT
|
|
|
872 >ORG <CODE
|
|
|
873 CLASS="PARAMETER"
|
|
|
874 >expr</CODE
|
|
|
875 ></DT
|
|
|
876 ><DD
|
|
|
877 ><P
|
|
|
878 >Set the assembly address. The address must be fully resolvable on the
|
|
|
879 first pass so no external or forward references are permitted. ORG is not
|
|
|
880 permitted within sections when outputting to object files. For the DECB
|
|
|
881 target, each ORG directive after which output is generated will cause
|
|
|
882 a new preamble to be output. ORG is only used to determine the addresses
|
|
|
883 of symbols when the raw target is used.</P
|
|
|
884 ></DD
|
|
|
885 ><DT
|
|
|
886 ><CODE
|
|
|
887 CLASS="PARAMETER"
|
|
|
888 >sym</CODE
|
|
|
889 > EQU <CODE
|
|
|
890 CLASS="PARAMETER"
|
|
|
891 >expr</CODE
|
|
|
892 >, <CODE
|
|
|
893 CLASS="PARAMETER"
|
|
|
894 >sym</CODE
|
|
|
895 > = <CODE
|
|
|
896 CLASS="PARAMETER"
|
|
|
897 >expr</CODE
|
|
|
898 ></DT
|
|
|
899 ><DD
|
|
|
900 ><P
|
|
|
901 >Define the value of <CODE
|
|
|
902 CLASS="PARAMETER"
|
|
|
903 >sym</CODE
|
|
|
904 > to be <CODE
|
|
|
905 CLASS="PARAMETER"
|
|
|
906 >expr</CODE
|
|
|
907 >.</P
|
|
|
908 ></DD
|
|
|
909 ><DT
|
|
|
910 ><CODE
|
|
|
911 CLASS="PARAMETER"
|
|
|
912 >sym</CODE
|
|
|
913 > SET <CODE
|
|
|
914 CLASS="PARAMETER"
|
|
|
915 >expr</CODE
|
|
|
916 ></DT
|
|
|
917 ><DD
|
|
|
918 ><P
|
|
|
919 >Define the value of <CODE
|
|
|
920 CLASS="PARAMETER"
|
|
|
921 >sym</CODE
|
|
|
922 > to be <CODE
|
|
|
923 CLASS="PARAMETER"
|
|
|
924 >expr</CODE
|
|
|
925 >.
|
|
|
926 Unlike EQU, SET permits symbols to be defined multiple times as long as SET
|
|
|
927 is used for all instances. Use of the symbol before the first SET statement
|
|
|
928 that sets its value is undefined.</P
|
|
|
929 ></DD
|
|
|
930 ><DT
|
|
|
931 >SETDP <CODE
|
|
|
932 CLASS="PARAMETER"
|
|
|
933 >expr</CODE
|
|
|
934 ></DT
|
|
|
935 ><DD
|
|
|
936 ><P
|
|
|
937 >Inform the assembler that it can assume the DP register contains
|
|
|
938 <CODE
|
|
|
939 CLASS="PARAMETER"
|
|
|
940 >expr</CODE
|
|
|
941 >. This directive is only advice to the assembler
|
|
|
942 to determine whether an address is in the direct page and has no effect
|
|
|
943 on the contents of the DP register. The value must be fully resolved during
|
|
|
944 the first assembly pass because it affects the sizes of subsequent instructions.</P
|
|
|
945 ><P
|
|
|
946 >This directive has no effect in the object file target.</P
|
|
|
947 ></DD
|
|
|
948 ><DT
|
|
|
949 >ALIGN <CODE
|
|
|
950 CLASS="PARAMETER"
|
|
|
951 >expr</CODE
|
|
|
952 ></DT
|
|
|
953 ><DD
|
|
|
954 ><P
|
|
|
955 >Force the current assembly address to be a multiple of <CODE
|
|
|
956 CLASS="PARAMETER"
|
|
|
957 >expr</CODE
|
|
|
958 >.
|
|
|
959 A series of NUL bytes is output to force the alignment, if required. The
|
|
|
960 alignment value must be fully resolved on the first pass because it affects
|
|
|
961 the addresses of subsquent instructions.</P
|
|
|
962 ><P
|
|
|
963 >This directive is not suitable for inclusion in the middle of actual
|
|
|
964 code. It is intended to appear where the bytes output will not be executed.</P
|
|
|
965 ></DD
|
|
|
966 ></DL
|
|
|
967 ></DIV
|
|
|
968 ></DIV
|
|
|
969 ><DIV
|
|
|
970 CLASS="SECTION"
|
|
|
971 ><HR><H3
|
|
|
972 CLASS="SECTION"
|
|
|
973 ><A
|
|
|
974 NAME="AEN285"
|
|
|
975 >3.6.3. Conditional Assembly</A
|
|
|
976 ></H3
|
|
|
977 ><P
|
|
|
978 >Portions of the source code can be excluded or included based on conditions
|
|
|
979 known at assembly time. Conditionals can be nested arbitrarily deeply. The
|
|
|
980 directives associated with conditional assembly are described in this section.</P
|
|
|
981 ><P
|
|
|
982 >All conditionals must be fully bracketed. That is, every conditional
|
|
|
983 statement must eventually be followed by an ENDC at the same level of nesting.</P
|
|
|
984 ><P
|
|
|
985 >Conditional expressions are only evaluated on the first assembly pass.
|
|
|
986 It is not possible to game the assembly process by having a conditional
|
|
|
987 change its value between assembly passes. Thus there is not and never will
|
|
|
988 be any equivalent of IFP1 or IFP2 as provided by other assemblers.</P
|
|
|
989 ><P
|
|
|
990 ></P
|
|
|
991 ><DIV
|
|
|
992 CLASS="VARIABLELIST"
|
|
|
993 ><DL
|
|
|
994 ><DT
|
|
|
995 >IFEQ <CODE
|
|
|
996 CLASS="PARAMETER"
|
|
|
997 >expr</CODE
|
|
|
998 ></DT
|
|
|
999 ><DD
|
|
|
1000 ><P
|
|
|
1001 >If <CODE
|
|
|
1002 CLASS="PARAMETER"
|
|
|
1003 >expr</CODE
|
|
|
1004 > evaluates to zero, the conditional
|
|
|
1005 will be considered true.</P
|
|
|
1006 ></DD
|
|
|
1007 ><DT
|
|
|
1008 >IFNE <CODE
|
|
|
1009 CLASS="PARAMETER"
|
|
|
1010 >expr</CODE
|
|
|
1011 >, IF <CODE
|
|
|
1012 CLASS="PARAMETER"
|
|
|
1013 >expr</CODE
|
|
|
1014 ></DT
|
|
|
1015 ><DD
|
|
|
1016 ><P
|
|
|
1017 >If <CODE
|
|
|
1018 CLASS="PARAMETER"
|
|
|
1019 >expr</CODE
|
|
|
1020 > evaluates to a non-zero value, the conditional
|
|
|
1021 will be considered true.</P
|
|
|
1022 ></DD
|
|
|
1023 ><DT
|
|
|
1024 >IFGT <CODE
|
|
|
1025 CLASS="PARAMETER"
|
|
|
1026 >expr</CODE
|
|
|
1027 ></DT
|
|
|
1028 ><DD
|
|
|
1029 ><P
|
|
|
1030 >If <CODE
|
|
|
1031 CLASS="PARAMETER"
|
|
|
1032 >expr</CODE
|
|
|
1033 > evaluates to a value greater than zero, the conditional
|
|
|
1034 will be considered true.</P
|
|
|
1035 ></DD
|
|
|
1036 ><DT
|
|
|
1037 >IFGE <CODE
|
|
|
1038 CLASS="PARAMETER"
|
|
|
1039 >expr</CODE
|
|
|
1040 ></DT
|
|
|
1041 ><DD
|
|
|
1042 ><P
|
|
|
1043 >If <CODE
|
|
|
1044 CLASS="PARAMETER"
|
|
|
1045 >expr</CODE
|
|
|
1046 > evaluates to a value greater than or equal to zero, the conditional
|
|
|
1047 will be considered true.</P
|
|
|
1048 ></DD
|
|
|
1049 ><DT
|
|
|
1050 >IFLT <CODE
|
|
|
1051 CLASS="PARAMETER"
|
|
|
1052 >expr</CODE
|
|
|
1053 ></DT
|
|
|
1054 ><DD
|
|
|
1055 ><P
|
|
|
1056 >If <CODE
|
|
|
1057 CLASS="PARAMETER"
|
|
|
1058 >expr</CODE
|
|
|
1059 > evaluates to a value less than zero, the conditional
|
|
|
1060 will be considered true.</P
|
|
|
1061 ></DD
|
|
|
1062 ><DT
|
|
|
1063 >IFLE <CODE
|
|
|
1064 CLASS="PARAMETER"
|
|
|
1065 >expr</CODE
|
|
|
1066 ></DT
|
|
|
1067 ><DD
|
|
|
1068 ><P
|
|
|
1069 >If <CODE
|
|
|
1070 CLASS="PARAMETER"
|
|
|
1071 >expr</CODE
|
|
|
1072 > evaluates to a value less than or equal to zero , the conditional
|
|
|
1073 will be considered true.</P
|
|
|
1074 ></DD
|
|
|
1075 ><DT
|
|
|
1076 >IFDEF <CODE
|
|
|
1077 CLASS="PARAMETER"
|
|
|
1078 >sym</CODE
|
|
|
1079 ></DT
|
|
|
1080 ><DD
|
|
|
1081 ><P
|
|
|
1082 >If <CODE
|
|
|
1083 CLASS="PARAMETER"
|
|
|
1084 >sym</CODE
|
|
|
1085 > is defined at this point in the assembly
|
|
|
1086 process, the conditional
|
|
|
1087 will be considered true.</P
|
|
|
1088 ></DD
|
|
|
1089 ><DT
|
|
|
1090 >IFNDEF <CODE
|
|
|
1091 CLASS="PARAMETER"
|
|
|
1092 >sym</CODE
|
|
|
1093 ></DT
|
|
|
1094 ><DD
|
|
|
1095 ><P
|
|
|
1096 >If <CODE
|
|
|
1097 CLASS="PARAMETER"
|
|
|
1098 >sym</CODE
|
|
|
1099 > is not defined at this point in the assembly
|
|
|
1100 process, the conditional
|
|
|
1101 will be considered true.</P
|
|
|
1102 ></DD
|
|
|
1103 ><DT
|
|
|
1104 >ELSE</DT
|
|
|
1105 ><DD
|
|
|
1106 ><P
|
|
|
1107 >If the preceding conditional at the same level of nesting was false, the
|
|
|
1108 statements following will be assembled. If the preceding conditional at
|
|
|
1109 the same level was true, the statements following will not be assembled.
|
|
|
1110 Note that the preceding conditional might have been another ELSE statement
|
|
|
1111 although this behaviour is not guaranteed to be supported in future versions
|
|
|
1112 of LWASM.</P
|
|
|
1113 ></DD
|
|
|
1114 ><DT
|
|
|
1115 >ENDC</DT
|
|
|
1116 ><DD
|
|
|
1117 ><P
|
|
|
1118 >This directive marks the end of a conditional construct. Every conditional
|
|
|
1119 construct must end with an ENDC directive.</P
|
|
|
1120 ></DD
|
|
|
1121 ></DL
|
|
|
1122 ></DIV
|
|
|
1123 ></DIV
|
|
|
1124 ><DIV
|
|
|
1125 CLASS="SECTION"
|
|
|
1126 ><HR><H3
|
|
|
1127 CLASS="SECTION"
|
|
|
1128 ><A
|
|
|
1129 NAME="AEN349"
|
|
|
1130 >3.6.4. Miscelaneous Directives</A
|
|
|
1131 ></H3
|
|
|
1132 ><P
|
|
|
1133 >This section includes directives that do not fit into the other
|
|
|
1134 categories.</P
|
|
|
1135 ><P
|
|
|
1136 ></P
|
|
|
1137 ><DIV
|
|
|
1138 CLASS="VARIABLELIST"
|
|
|
1139 ><DL
|
|
|
1140 ><DT
|
|
|
1141 >INCLUDE <CODE
|
|
|
1142 CLASS="PARAMETER"
|
|
|
1143 >filename</CODE
|
|
|
1144 ></DT
|
|
|
1145 ><DD
|
|
|
1146 ><P
|
|
|
1147 >Include the contents of <CODE
|
|
|
1148 CLASS="PARAMETER"
|
|
|
1149 >filename</CODE
|
|
|
1150 > at this point in
|
|
|
1151 the assembly as though it were a part of the file currently being processed.
|
|
|
1152 Note that whitespace cannot appear in the name of the file.</P
|
|
|
1153 ></DD
|
|
|
1154 ><DT
|
|
|
1155 >END <CODE
|
|
|
1156 CLASS="PARAMETER"
|
|
|
1157 >[expr]</CODE
|
|
|
1158 ></DT
|
|
|
1159 ><DD
|
|
|
1160 ><P
|
|
|
1161 >This directive causes the assembler to stop assembling immediately as though
|
|
|
1162 it ran out of input. For the DECB target only, <CODE
|
|
|
1163 CLASS="PARAMETER"
|
|
|
1164 >expr</CODE
|
|
|
1165 >
|
|
|
1166 can be used to set the execution address of the resulting binary. For all
|
|
|
1167 other targets, specifying <CODE
|
|
|
1168 CLASS="PARAMETER"
|
|
|
1169 >expr</CODE
|
|
|
1170 > will cause an error.</P
|
|
|
1171 ></DD
|
|
|
1172 ><DT
|
|
|
1173 >ERROR <CODE
|
|
|
1174 CLASS="PARAMETER"
|
|
|
1175 >string</CODE
|
|
|
1176 ></DT
|
|
|
1177 ><DD
|
|
|
1178 ><P
|
|
|
1179 >Causes a custom error message to be printed at this line. This will cause
|
|
|
1180 assembly to fail. This directive is most useful inside conditional constructs
|
|
|
1181 to cause assembly to fail if some condition that is known bad happens.</P
|
|
|
1182 ></DD
|
|
|
1183 ><DT
|
|
|
1184 >.MODULE <CODE
|
|
|
1185 CLASS="PARAMETER"
|
|
|
1186 >string</CODE
|
|
|
1187 ></DT
|
|
|
1188 ><DD
|
|
|
1189 ><P
|
|
|
1190 >This directive is ignored for most output targets. If the output target
|
|
|
1191 supports encoding a module name into it, <CODE
|
|
|
1192 CLASS="PARAMETER"
|
|
|
1193 >string</CODE
|
|
|
1194 >
|
|
|
1195 will be used as the module name.</P
|
|
|
1196 ><P
|
|
|
1197 >As of version 2.2, no supported output targets support this directive.</P
|
|
|
1198 ></DD
|
|
|
1199 ></DL
|
|
|
1200 ></DIV
|
|
|
1201 ></DIV
|
|
|
1202 ></DIV
|
|
|
1203 ><DIV
|
|
|
1204 CLASS="SECTION"
|
|
|
1205 ><HR><H2
|
|
|
1206 CLASS="SECTION"
|
|
|
1207 ><A
|
|
|
1208 NAME="AEN378"
|
|
|
1209 >3.7. Macros</A
|
|
|
1210 ></H2
|
|
|
1211 ><P
|
|
|
1212 >LWASM is a macro assembler. A macro is simply a name that stands in for a
|
|
|
1213 series of instructions. Once a macro is defined, it is used like any other
|
|
|
1214 assembler directive. Defining a macro can be considered equivalent to adding
|
|
|
1215 additional assembler directives.</P
|
|
|
1216 ><P
|
|
|
1217 >Macros my accept parameters. These parameters are referenced within
|
|
|
1218 a macro by the a backslash ("\") followed by a digit 1 through 9 for the first
|
|
|
1219 through ninth parameters. They may also be referenced by enclosing the
|
|
|
1220 decimal parameter number in braces ("{num}"). These parameter references
|
|
|
1221 are replaced with the verbatim text of the parameter passed to the macro. A
|
|
|
1222 reference to a non-existent parameter will be replaced by an empty string.
|
|
|
1223 Macro parameters are expanded everywhere on each source line. That means
|
|
|
1224 the parameter to a macro could be used as a symbol or it could even appear
|
|
|
1225 in a comment or could cause an entire source line to be commented out
|
|
|
1226 when the macro is expanded.</P
|
|
|
1227 ><P
|
|
|
1228 >Parameters passed to a macro are separated by commas and the parameter list
|
|
|
1229 is terminated by any whitespace. This means that neither a comma nor whitespace
|
|
|
1230 may be included in a macro parameter.</P
|
|
|
1231 ><P
|
|
|
1232 >Macro expansion is done recursively. That is, within a macro, macros are
|
|
|
1233 expanded. This can lead to infinite loops in macro expansion. If the assembler
|
|
|
1234 hangs for a long time while assembling a file that uses macros, this may be
|
|
|
1235 the reason.</P
|
|
|
1236 ><P
|
|
|
1237 >Each macro expansion receives its own local symbol context which is not
|
|
|
1238 inherited by any macros called by it nor is it inherited from the context
|
|
|
1239 the macro was instantiated in. That means it is possible to use local symbols
|
|
|
1240 within macros without having them collide with symbols in other macros or
|
|
|
1241 outside the macro itself. However, this also means that using a local symbol
|
|
|
1242 as a parameter to a macro, while legal, will not do what it would seem to do
|
|
|
1243 as it will result in looking up the local symbol in the macro's symbol context
|
|
|
1244 rather than the enclosing context where it came from, likely yielding either
|
|
|
1245 an undefined symbol error or bizarre assembly results.</P
|
|
|
1246 ><P
|
|
|
1247 >Note that there is no way to define a macro as local to a symbol context. All
|
|
|
1248 macros are part of the global macro namespace. However, macros have a separate
|
|
|
1249 namespace from symbols so it is possible to have a symbol with the same name
|
|
|
1250 as a macro.</P
|
|
|
1251 ><P
|
|
|
1252 >Macros are defined only during the first pass. Macro expansion also
|
|
|
1253 only occurs during the first pass. On the second pass, the macro
|
|
|
1254 definition is simply ignored. Macros must be defined before they are used.</P
|
|
|
1255 ><P
|
|
|
1256 >The following directives are used when defining macros.</P
|
|
|
1257 ><P
|
|
|
1258 ></P
|
|
|
1259 ><DIV
|
|
|
1260 CLASS="VARIABLELIST"
|
|
|
1261 ><DL
|
|
|
1262 ><DT
|
|
|
1263 ><CODE
|
|
|
1264 CLASS="PARAMETER"
|
|
|
1265 >macroname</CODE
|
|
|
1266 > MACRO</DT
|
|
|
1267 ><DD
|
|
|
1268 ><P
|
|
|
1269 >This directive is used to being the definition of a macro called
|
|
|
1270 <CODE
|
|
|
1271 CLASS="PARAMETER"
|
|
|
1272 >macroname</CODE
|
|
|
1273 >. If <CODE
|
|
|
1274 CLASS="PARAMETER"
|
|
|
1275 >macroname</CODE
|
|
|
1276 > already
|
|
|
1277 exists, it is considered an error. Attempting to define a macro within a
|
|
|
1278 macro is undefined. It may work and it may not so the behaviour should not
|
|
|
1279 be relied upon.</P
|
|
|
1280 ></DD
|
|
|
1281 ><DT
|
|
|
1282 >ENDM</DT
|
|
|
1283 ><DD
|
|
|
1284 ><P
|
|
|
1285 >This directive indicates the end of the macro currently being defined. It
|
|
|
1286 causes the assembler to resume interpreting source lines as normal.</P
|
|
|
1287 ></DD
|
|
|
1288 ></DL
|
|
|
1289 ></DIV
|
|
|
1290 ></DIV
|
|
|
1291 ><DIV
|
|
|
1292 CLASS="SECTION"
|
|
|
1293 ><HR><H2
|
|
|
1294 CLASS="SECTION"
|
|
|
1295 ><A
|
|
|
1296 NAME="AEN400"
|
|
|
1297 >3.8. Object Files and Sections</A
|
|
|
1298 ></H2
|
|
|
1299 ><P
|
|
|
1300 >The object file target is very useful for large project because it allows
|
|
|
1301 multiple files to be assembled independently and then linked into the final
|
|
|
1302 binary at a later time. It allows only the small portion of the project
|
|
|
1303 that was modified to be re-assembled rather than requiring the entire set
|
|
|
1304 of source code to be available to the assembler in a single assembly process.
|
|
|
1305 This can be particularly important if there are a large number of macros,
|
|
|
1306 symbol definitions, or other metadata that uses resources at assembly time.
|
|
|
1307 By far the largest benefit, however, is keeping the source files small enough
|
|
|
1308 for a mere mortal to find things in them.</P
|
|
|
1309 ><P
|
|
|
1310 >With multi-file projects, there needs to be a means of resolving references to
|
|
|
1311 symbols in other source files. These are known as external references. The
|
|
|
1312 addresses of these symbols cannot be known until the linker joins all the
|
|
|
1313 object files into a single binary. This means that the assembler must be
|
|
|
1314 able to output the object code without knowing the value of the symbol. This
|
|
|
1315 places some restrictions on the code generated by the assembler. For
|
|
|
1316 example, the assembler cannot generate direct page addressing for instructions
|
|
|
1317 that reference external symbols because the address of the symbol may not
|
|
|
1318 be in the direct page. Similarly, relative branches and PC relative addressing
|
|
|
1319 cannot be used in their eight bit forms. Everything that must be resolved
|
|
|
1320 by the linker must be assembled to use the largest address size possible to
|
|
|
1321 allow the linker to fill in the correct value at link time. Note that the
|
|
|
1322 same problem applies to absolute address references as well, even those in
|
|
|
1323 the same source file, because the address is not known until link time.</P
|
|
|
1324 ><P
|
|
|
1325 >It is often desired in multi-file projects to have code of various types grouped
|
|
|
1326 together in the final binary generated by the linker as well. The same applies
|
|
|
1327 to data. In order for the linker to do that, the bits that are to be grouped
|
|
|
1328 must be tagged in some manner. This is where the concept of sections comes in.
|
|
|
1329 Each chunk of code or data is part of a section in the object file. Then,
|
|
|
1330 when the linker reads all the object files, it coalesces all sections of the
|
|
|
1331 same name into a single section and then considers it as a unit.</P
|
|
|
1332 ><P
|
|
|
1333 >The existence of sections, however, raises a problem for symbols even
|
|
|
1334 within the same source file. Thus, the assembler must treat symbols from
|
|
|
1335 different sections within the same source file in the same manner as external
|
|
|
1336 symbols. That is, it must leave them for the linker to resolve at link time,
|
|
|
1337 with all the limitations that entails.</P
|
|
|
1338 ><P
|
|
|
1339 >In the object file target mode, LWASM requires all source lines that
|
|
|
1340 cause bytes to be output to be inside a section. Any directives that do
|
|
|
1341 not cause any bytes to be output can appear outside of a section. This includes
|
|
|
1342 such things as EQU or RMB. Even ORG can appear outside a section. ORG, however,
|
|
|
1343 makes no sense within a section because it is the linker that determines
|
|
|
1344 the starting address of the section's code, not the assembler.</P
|
|
|
1345 ><P
|
|
|
1346 >All symbols defined globally in the assembly process are local to the
|
|
|
1347 source file and cannot be exported. All symbols defined within a section are
|
|
|
1348 considered local to the source file unless otherwise explicitly exported.
|
|
|
1349 Symbols referenced from external source files must be declared external,
|
|
|
1350 either explicitly or by asking the assembler to assume that all undefined
|
|
|
1351 symbols are external.</P
|
|
|
1352 ><P
|
|
|
1353 >It is often handy to define a number of memory addresses that will be
|
|
|
1354 used for data at run-time but which need not be included in the binary file.
|
|
|
1355 These memory addresses are not initialized until run-time, either by the
|
|
|
1356 program itself or by the program loader, depending on the operating environment.
|
|
|
1357 Such sections are often known as BSS sections. LWASM supports generating
|
|
|
1358 sections with a BSS attribute set which causes the section definition including
|
|
|
1359 symbols exported from that section and those symbols required to resolve
|
|
|
1360 references from the local file, but with no actual code in the object file.
|
|
|
1361 It is illegal for any source lines within a BSS flagged section to cause any
|
|
|
1362 bytes to be output.</P
|
|
|
1363 ><P
|
|
|
1364 >The following directives apply to section handling.</P
|
|
|
1365 ><P
|
|
|
1366 ></P
|
|
|
1367 ><DIV
|
|
|
1368 CLASS="VARIABLELIST"
|
|
|
1369 ><DL
|
|
|
1370 ><DT
|
|
|
1371 >SECTION <CODE
|
|
|
1372 CLASS="PARAMETER"
|
|
|
1373 >name[,flags]</CODE
|
|
|
1374 >, SECT <CODE
|
|
|
1375 CLASS="PARAMETER"
|
|
|
1376 >name[,flags]</CODE
|
|
|
1377 >, .AREA <CODE
|
|
|
1378 CLASS="PARAMETER"
|
|
|
1379 >name[,flags]</CODE
|
|
|
1380 ></DT
|
|
|
1381 ><DD
|
|
|
1382 ><P
|
|
|
1383 >Instructs the assembler that the code following this directive is to be
|
|
|
1384 considered part of the section <CODE
|
|
|
1385 CLASS="PARAMETER"
|
|
|
1386 >name</CODE
|
|
|
1387 >. A section name
|
|
|
1388 may appear multiple times in which case it is as though all the code from
|
|
|
1389 all the instances of that section appeared adjacent within the source file.
|
|
|
1390 However, <CODE
|
|
|
1391 CLASS="PARAMETER"
|
|
|
1392 >flags</CODE
|
|
|
1393 > may only be specified on the first
|
|
|
1394 instance of the section.</P
|
|
|
1395 ><P
|
|
|
1396 >There is a single flag supported in <CODE
|
|
|
1397 CLASS="PARAMETER"
|
|
|
1398 >flags</CODE
|
|
|
1399 >. The
|
|
|
1400 flag <CODE
|
|
|
1401 CLASS="PARAMETER"
|
|
|
1402 >bss</CODE
|
|
|
1403 > will cause the section to be treated as a BSS
|
|
|
1404 section and, thus, no code will be included in the object file nor will any
|
|
|
1405 bytes be permitted to be output.</P
|
|
|
1406 ><P
|
|
|
1407 >If the section name is "bss" or ".bss" in any combination of upper and
|
|
|
1408 lower case, the section is assumed to be a BSS section. In that case,
|
|
|
1409 the flag <CODE
|
|
|
1410 CLASS="PARAMETER"
|
|
|
1411 >!bss</CODE
|
|
|
1412 > can be used to override this assumption.</P
|
|
|
1413 ><P
|
|
|
1414 >If assembly is already happening within a section, the section is implicitly
|
|
|
1415 ended and the new section started. This is not considered an error although
|
|
|
1416 it is recommended that all sections be explicitly closed.</P
|
|
|
1417 ></DD
|
|
|
1418 ><DT
|
|
|
1419 >ENDSECTION, ENDSECT, ENDS</DT
|
|
|
1420 ><DD
|
|
|
1421 ><P
|
|
|
1422 >This directive ends the current section. This puts assembly outside of any
|
|
|
1423 sections until the next SECTION directive.</P
|
|
|
1424 ></DD
|
|
|
1425 ><DT
|
|
|
1426 ><CODE
|
|
|
1427 CLASS="PARAMETER"
|
|
|
1428 >sym</CODE
|
|
|
1429 > EXTERN, <CODE
|
|
|
1430 CLASS="PARAMETER"
|
|
|
1431 >sym</CODE
|
|
|
1432 > EXTERNAL, <CODE
|
|
|
1433 CLASS="PARAMETER"
|
|
|
1434 >sym</CODE
|
|
|
1435 > IMPORT</DT
|
|
|
1436 ><DD
|
|
|
1437 ><P
|
|
|
1438 >This directive defines <CODE
|
|
|
1439 CLASS="PARAMETER"
|
|
|
1440 >sym</CODE
|
|
|
1441 > as an external symbol.
|
|
|
1442 This directive may occur at any point in the source code. EXTERN definitions
|
|
|
1443 are resolved on the first pass so an EXTERN definition anywhere in the
|
|
|
1444 source file is valid for the entire file. The use of this directive is
|
|
|
1445 optional when the assembler is instructed to assume that all undefined
|
|
|
1446 symbols are external. In fact, in that mode, if the symbol is referenced
|
|
|
1447 before the EXTERN directive, an error will occur.</P
|
|
|
1448 ></DD
|
|
|
1449 ><DT
|
|
|
1450 ><CODE
|
|
|
1451 CLASS="PARAMETER"
|
|
|
1452 >sym</CODE
|
|
|
1453 > EXPORT, <CODE
|
|
|
1454 CLASS="PARAMETER"
|
|
|
1455 >sym</CODE
|
|
|
1456 > .GLOBL, EXPORT <CODE
|
|
|
1457 CLASS="PARAMETER"
|
|
|
1458 >sym</CODE
|
|
|
1459 >, .GLOBL <CODE
|
|
|
1460 CLASS="PARAMETER"
|
|
|
1461 >sym</CODE
|
|
|
1462 ></DT
|
|
|
1463 ><DD
|
|
|
1464 ><P
|
|
|
1465 >This directive defines <CODE
|
|
|
1466 CLASS="PARAMETER"
|
|
|
1467 >sym</CODE
|
|
|
1468 > as an exported symbol.
|
|
|
1469 This directive may occur at any point in the source code, even before the
|
|
|
1470 definition of the exported symbol.</P
|
|
|
1471 ><P
|
|
|
1472 >Note that <CODE
|
|
|
1473 CLASS="PARAMETER"
|
|
|
1474 >sym</CODE
|
|
|
1475 > may appear as the operand or as the
|
|
|
1476 statement's symbol. If there is a symbol on the statement, that will
|
|
|
1477 take precedence over any operand that is present.</P
|
|
|
1478 ></DD
|
|
|
1479 ></DL
|
|
|
1480 ></DIV
|
|
|
1481 ></DIV
|
|
|
1482 ><DIV
|
|
|
1483 CLASS="SECTION"
|
|
|
1484 ><HR><H2
|
|
|
1485 CLASS="SECTION"
|
|
|
1486 ><A
|
|
|
1487 NAME="AEN458"
|
|
|
1488 >3.9. Assembler Modes and Pragmas</A
|
|
|
1489 ></H2
|
|
|
1490 ><P
|
|
|
1491 >There are a number of options that affect the way assembly is performed.
|
|
|
1492 Some of these options can only be specified on the command line because
|
|
|
1493 they determine something absolute about the assembly process. These include
|
|
|
1494 such things as the output target. Other things may be switchable during
|
|
|
1495 the assembly process. These are known as pragmas and are, by definition,
|
|
|
1496 not portable between assemblers.</P
|
|
|
1497 ><P
|
|
|
1498 >LWASM supports a number of pragmas that affect code generation or
|
|
|
1499 otherwise affect the behaviour of the assembler. These may be specified by
|
|
|
1500 way of a command line option or by assembler directives. The directives
|
|
|
1501 are as follows.</P
|
|
|
1502 ><P
|
|
|
1503 ></P
|
|
|
1504 ><DIV
|
|
|
1505 CLASS="VARIABLELIST"
|
|
|
1506 ><DL
|
|
|
1507 ><DT
|
|
|
1508 >PRAGMA <CODE
|
|
|
1509 CLASS="PARAMETER"
|
|
|
1510 >pragma[,...]</CODE
|
|
|
1511 ></DT
|
|
|
1512 ><DD
|
|
|
1513 ><P
|
|
|
1514 >Specifies that the assembler should bring into force all <CODE
|
|
|
1515 CLASS="PARAMETER"
|
|
|
1516 >pragma</CODE
|
|
|
1517 >s
|
|
|
1518 specified. Any unrecognized pragma will cause an assembly error. The new
|
|
|
1519 pragmas will take effect immediately. This directive should be used when
|
|
|
1520 the program will assemble incorrectly if the pragma is ignored or not supported.</P
|
|
|
1521 ></DD
|
|
|
1522 ><DT
|
|
|
1523 >*PRAGMA <CODE
|
|
|
1524 CLASS="PARAMETER"
|
|
|
1525 >pragma[,...]</CODE
|
|
|
1526 ></DT
|
|
|
1527 ><DD
|
|
|
1528 ><P
|
|
|
1529 >This is identical to the PRAGMA directive except no error will occur with
|
|
|
1530 unrecognized or unsupported pragmas. This directive, by virtue of starting
|
|
|
1531 with a comment character, will also be ignored by assemblers that do not
|
|
|
1532 support this directive. Use this variation if the pragma is not required
|
|
|
1533 for correct functioning of the code.</P
|
|
|
1534 ></DD
|
|
|
1535 ></DL
|
|
|
1536 ></DIV
|
|
|
1537 ><P
|
|
|
1538 >Each pragma supported has a positive version and a negative version.
|
|
|
1539 The positive version enables the pragma while the negative version disables
|
|
|
1540 it. The negatitve version is simply the positive version with "no" prefixed
|
|
|
1541 to it. For instance, "pragma" vs. "nopragma". Only the positive version is
|
|
|
1542 listed below.</P
|
|
|
1543 ><P
|
|
|
1544 >Pragmas are not case sensitive.</P
|
|
|
1545 ><P
|
|
|
1546 ></P
|
|
|
1547 ><DIV
|
|
|
1548 CLASS="VARIABLELIST"
|
|
|
1549 ><DL
|
|
|
1550 ><DT
|
|
|
1551 >index0tonone</DT
|
|
|
1552 ><DD
|
|
|
1553 ><P
|
|
|
1554 >When in force, this pragma enables an optimization affecting indexed addressing
|
|
|
1555 modes. When the offset expression in an indexed mode evaluates to zero but is
|
|
|
1556 not explicity written as 0, this will replace the operand with the equivalent
|
|
|
1557 no offset mode, thus creating slightly faster code. Because of the advantages
|
|
|
1558 of this optimization, it is enabled by default.</P
|
|
|
1559 ></DD
|
|
|
1560 ><DT
|
|
|
1561 >cescapes</DT
|
|
|
1562 ><DD
|
|
|
1563 ><P
|
|
|
1564 >This pragma will cause strings in the FCC, FCS, and FCN pseudo operations to
|
|
|
1565 have C-style escape sequences interpreted. The one departure from the official
|
|
|
1566 spec is that unrecognized escape sequences will return either the character
|
|
|
1567 immediately following the backslash or some undefined value. Do not rely
|
|
|
1568 on the behaviour of undefined escape sequences.</P
|
|
|
1569 ></DD
|
|
|
1570 ><DT
|
|
|
1571 >undefextern</DT
|
|
|
1572 ><DD
|
|
|
1573 ><P
|
|
|
1574 >This pragma is only valid for targets that support external references. When in
|
|
|
1575 force, if the assembler sees an undefined symbol on the second pass, it will
|
|
|
1576 automatically define it as an external symbol. This automatic definition will
|
|
|
1577 apply for the remainder of the assembly process, even if the pragma is
|
|
|
1578 subsequently turned off. Because this behaviour would be potentially surprising,
|
|
|
1579 this pragma defaults to off.</P
|
|
|
1580 ><P
|
|
|
1581 >The primary use for this pragma is for projects that share a large number of
|
|
|
1582 symbols between source files. In such cases, it is impractical to enumerate
|
|
|
1583 all the external references in every source file. This allows the assembler
|
|
|
1584 and linker to do the heavy lifting while not preventing a particular source
|
|
|
1585 module from defining a local symbol of the same name as an external symbol
|
|
|
1586 if it does not need the external symbol. (This pragma will not cause an
|
|
|
1587 automatic external definition if there is already a locally defined symbol.)</P
|
|
|
1588 ><P
|
|
|
1589 >This pragma will often be specified on the command line for large projects.
|
|
|
1590 However, depending on the specific dynamics of the project, it may be sufficient
|
|
|
1591 for one or two files to use this pragma internally.</P
|
|
|
1592 ></DD
|
|
|
1593 ></DL
|
|
|
1594 ></DIV
|
|
|
1595 ></DIV
|
|
|
1596 ></DIV
|
|
|
1597 ><DIV
|
|
|
1598 CLASS="CHAPTER"
|
|
|
1599 ><HR><H1
|
|
|
1600 ><A
|
|
|
1601 NAME="AEN491"
|
|
|
1602 ></A
|
|
|
1603 >Chapter 4. LWLINK</H1
|
|
|
1604 ><P
|
|
|
1605 >The LWTOOLS linker is called LWLINK. This chapter documents the various features
|
|
|
1606 of the linker.</P
|
|
|
1607 ><DIV
|
|
|
1608 CLASS="SECTION"
|
|
|
1609 ><HR><H2
|
|
|
1610 CLASS="SECTION"
|
|
|
1611 ><A
|
|
|
1612 NAME="AEN494"
|
|
|
1613 >4.1. Command Line Options</A
|
|
|
1614 ></H2
|
|
|
1615 ><P
|
|
|
1616 >The binary for LWLINK is called "lwlink". Note that the binary is in lower
|
|
|
1617 case. lwlink takes the following command line arguments.</P
|
|
|
1618 ><P
|
|
|
1619 ></P
|
|
|
1620 ><DIV
|
|
|
1621 CLASS="VARIABLELIST"
|
|
|
1622 ><DL
|
|
|
1623 ><DT
|
|
|
1624 ><CODE
|
|
|
1625 CLASS="OPTION"
|
|
|
1626 >--decb</CODE
|
|
|
1627 >, <CODE
|
|
|
1628 CLASS="OPTION"
|
|
|
1629 >-b</CODE
|
|
|
1630 ></DT
|
|
|
1631 ><DD
|
|
|
1632 ><P
|
|
|
1633 >Selects the DECB output format target. This is equivalent to <CODE
|
|
|
1634 CLASS="OPTION"
|
|
|
1635 >--format=decb</CODE
|
|
|
1636 ></P
|
|
|
1637 ></DD
|
|
|
1638 ><DT
|
|
|
1639 ><CODE
|
|
|
1640 CLASS="OPTION"
|
|
|
1641 >--output=FILE</CODE
|
|
|
1642 >, <CODE
|
|
|
1643 CLASS="OPTION"
|
|
|
1644 >-o FILE</CODE
|
|
|
1645 ></DT
|
|
|
1646 ><DD
|
|
|
1647 ><P
|
|
|
1648 >This option specifies the name of the output file. If not specified, the
|
|
|
1649 default is <CODE
|
|
|
1650 CLASS="OPTION"
|
|
|
1651 >a.out</CODE
|
|
|
1652 >.</P
|
|
|
1653 ></DD
|
|
|
1654 ><DT
|
|
|
1655 ><CODE
|
|
|
1656 CLASS="OPTION"
|
|
|
1657 >--format=TYPE</CODE
|
|
|
1658 >, <CODE
|
|
|
1659 CLASS="OPTION"
|
|
|
1660 >-f TYPE</CODE
|
|
|
1661 ></DT
|
|
|
1662 ><DD
|
|
|
1663 ><P
|
|
|
1664 >This option specifies the output format. Valid values are <CODE
|
|
|
1665 CLASS="OPTION"
|
|
|
1666 >decb</CODE
|
|
|
1667 >
|
|
|
1668 and <CODE
|
|
|
1669 CLASS="OPTION"
|
|
|
1670 >raw</CODE
|
|
|
1671 ></P
|
|
|
1672 ></DD
|
|
|
1673 ><DT
|
|
|
1674 ><CODE
|
|
|
1675 CLASS="OPTION"
|
|
|
1676 >--raw</CODE
|
|
|
1677 >, <CODE
|
|
|
1678 CLASS="OPTION"
|
|
|
1679 >-r</CODE
|
|
|
1680 ></DT
|
|
|
1681 ><DD
|
|
|
1682 ><P
|
|
|
1683 >This option specifies the raw output format.
|
|
|
1684 It is equivalent to <CODE
|
|
|
1685 CLASS="OPTION"
|
|
|
1686 >--format=raw</CODE
|
|
|
1687 >.
|
|
|
1688 and <CODE
|
|
|
1689 CLASS="OPTION"
|
|
|
1690 >raw</CODE
|
|
|
1691 ></P
|
|
|
1692 ></DD
|
|
|
1693 ><DT
|
|
|
1694 ><CODE
|
|
|
1695 CLASS="OPTION"
|
|
|
1696 >--script=FILE</CODE
|
|
|
1697 >, <CODE
|
|
|
1698 CLASS="OPTION"
|
|
|
1699 >-s</CODE
|
|
|
1700 ></DT
|
|
|
1701 ><DD
|
|
|
1702 ><P
|
|
|
1703 >This option allows specifying a linking script to override the linker's
|
|
|
1704 built in defaults.</P
|
|
|
1705 ></DD
|
|
|
1706 ><DT
|
|
|
1707 ><CODE
|
|
|
1708 CLASS="OPTION"
|
|
|
1709 >--section-base=SECT=BASE</CODE
|
|
|
1710 ></DT
|
|
|
1711 ><DD
|
|
|
1712 ><P
|
|
|
1713 >Cause section SECT to load at base address BASE. This will be prepended
|
|
|
1714 to the built-in link script. It is ignored if a link script is provided.</P
|
|
|
1715 ></DD
|
|
|
1716 ><DT
|
|
|
1717 ><CODE
|
|
|
1718 CLASS="OPTION"
|
|
|
1719 >--map=FILE</CODE
|
|
|
1720 >, <CODE
|
|
|
1721 CLASS="OPTION"
|
|
|
1722 >-m FILE</CODE
|
|
|
1723 ></DT
|
|
|
1724 ><DD
|
|
|
1725 ><P
|
|
|
1726 >This will output a description of the link result to FILE.</P
|
|
|
1727 ></DD
|
|
|
1728 ><DT
|
|
|
1729 ><CODE
|
|
|
1730 CLASS="OPTION"
|
|
|
1731 >--library=LIBSPEC</CODE
|
|
|
1732 >, <CODE
|
|
|
1733 CLASS="OPTION"
|
|
|
1734 >-l LIBSPEC</CODE
|
|
|
1735 ></DT
|
|
|
1736 ><DD
|
|
|
1737 ><P
|
|
|
1738 >Load a library using the library search path. LIBSPEC will have "lib" prepended
|
|
|
1739 and ".a" appended.</P
|
|
|
1740 ></DD
|
|
|
1741 ><DT
|
|
|
1742 ><CODE
|
|
|
1743 CLASS="OPTION"
|
|
|
1744 >--library-path=DIR</CODE
|
|
|
1745 >, <CODE
|
|
|
1746 CLASS="OPTION"
|
|
|
1747 >-L DIR</CODE
|
|
|
1748 ></DT
|
|
|
1749 ><DD
|
|
|
1750 ><P
|
|
|
1751 >Add DIR to the library search path.</P
|
|
|
1752 ></DD
|
|
|
1753 ><DT
|
|
|
1754 ><CODE
|
|
|
1755 CLASS="OPTION"
|
|
|
1756 >--debug</CODE
|
|
|
1757 >, <CODE
|
|
|
1758 CLASS="OPTION"
|
|
|
1759 >-d</CODE
|
|
|
1760 ></DT
|
|
|
1761 ><DD
|
|
|
1762 ><P
|
|
|
1763 >This option increases the debugging level. It is only useful for LWTOOLS
|
|
|
1764 developers.</P
|
|
|
1765 ></DD
|
|
|
1766 ><DT
|
|
|
1767 ><CODE
|
|
|
1768 CLASS="OPTION"
|
|
|
1769 >--help</CODE
|
|
|
1770 >, <CODE
|
|
|
1771 CLASS="OPTION"
|
|
|
1772 >-?</CODE
|
|
|
1773 ></DT
|
|
|
1774 ><DD
|
|
|
1775 ><P
|
|
|
1776 >This provides a listing of command line options and a brief description
|
|
|
1777 of each.</P
|
|
|
1778 ></DD
|
|
|
1779 ><DT
|
|
|
1780 ><CODE
|
|
|
1781 CLASS="OPTION"
|
|
|
1782 >--usage</CODE
|
|
|
1783 ></DT
|
|
|
1784 ><DD
|
|
|
1785 ><P
|
|
|
1786 >This will display a usage summary.
|
|
|
1787 of each.</P
|
|
|
1788 ></DD
|
|
|
1789 ><DT
|
|
|
1790 ><CODE
|
|
|
1791 CLASS="OPTION"
|
|
|
1792 >--version</CODE
|
|
|
1793 >, <CODE
|
|
|
1794 CLASS="OPTION"
|
|
|
1795 >-V</CODE
|
|
|
1796 ></DT
|
|
|
1797 ><DD
|
|
|
1798 ><P
|
|
|
1799 >This will display the version of LWLINK.</P
|
|
|
1800 ></DD
|
|
|
1801 ></DL
|
|
|
1802 ></DIV
|
|
|
1803 ></DIV
|
|
|
1804 ><DIV
|
|
|
1805 CLASS="SECTION"
|
|
|
1806 ><HR><H2
|
|
|
1807 CLASS="SECTION"
|
|
|
1808 ><A
|
|
|
1809 NAME="AEN591"
|
|
|
1810 >4.2. Linker Operation</A
|
|
|
1811 ></H2
|
|
|
1812 ><P
|
|
|
1813 > LWLINK takes one or more files in supported input formats and links them
|
|
|
1814 into a single binary. Currently supported formats are the LWTOOLS object
|
|
|
1815 file format and the archive format used by LWAR. While the precise method is
|
|
|
1816 slightly different, linking can be conceptualized as the following steps. </P
|
|
|
1817 ><P
|
|
|
1818 ></P
|
|
|
1819 ><OL
|
|
|
1820 TYPE="1"
|
|
|
1821 ><LI
|
|
|
1822 ><P
|
|
|
1823 >First, the linker loads a linking script. If no script is specified, it
|
|
|
1824 loads a built-in default script based on the output format selected. This
|
|
|
1825 script tells the linker how to lay out the various sections in the final
|
|
|
1826 binary.</P
|
|
|
1827 ></LI
|
|
|
1828 ><LI
|
|
|
1829 ><P
|
|
|
1830 >Next, the linker reads all the input files into memory. At this time, it
|
|
|
1831 flags any format errors in those files. It constructs a table of symbols
|
|
|
1832 for each object at this time.</P
|
|
|
1833 ></LI
|
|
|
1834 ><LI
|
|
|
1835 ><P
|
|
|
1836 >The linker then proceeds with organizing the sections loaded from each file
|
|
|
1837 according to the linking script. As it does so, it is able to assign addresses
|
|
|
1838 to each symbol defined in each object file. At this time, the linker may
|
|
|
1839 also collapse different instances of the same section name into a single
|
|
|
1840 section by appending the data from each subsequent instance of the section
|
|
|
1841 to the first instance of the section.</P
|
|
|
1842 ></LI
|
|
|
1843 ><LI
|
|
|
1844 ><P
|
|
|
1845 >Next, the linker looks through every object file for every incomplete reference.
|
|
|
1846 It then attempts to fully resolve that reference. If it cannot do so, it
|
|
|
1847 throws an error. Once a reference is resolved, the value is placed into
|
|
|
1848 the binary code at the specified section. It should be noted that an
|
|
|
1849 incomplete reference can reference either a symbol internal to the object
|
|
|
1850 file or an external symbol which is in the export list of another object
|
|
|
1851 file.</P
|
|
|
1852 ></LI
|
|
|
1853 ><LI
|
|
|
1854 ><P
|
|
|
1855 >If all of the above steps are successful, the linker opens the output file
|
|
|
1856 and actually constructs the binary.</P
|
|
|
1857 ></LI
|
|
|
1858 ></OL
|
|
|
1859 ></DIV
|
|
|
1860 ><DIV
|
|
|
1861 CLASS="SECTION"
|
|
|
1862 ><HR><H2
|
|
|
1863 CLASS="SECTION"
|
|
|
1864 ><A
|
|
|
1865 NAME="AEN605"
|
|
|
1866 >4.3. Linking Scripts</A
|
|
|
1867 ></H2
|
|
|
1868 ><P
|
|
|
1869 >A linker script is used to instruct the linker about how to assemble the
|
|
|
1870 various sections into a completed binary. It consists of a series of
|
|
|
1871 directives which are considered in the order they are encountered.</P
|
|
|
1872 ><P
|
|
|
1873 >The sections will appear in the resulting binary in the order they are
|
|
|
1874 specified in the script file. If a referenced section is not found, the linker will behave as though the
|
|
|
1875 section did exist but had a zero size, no relocations, and no exports.
|
|
|
1876 A section should only be referenced once. Any subsequent references will have
|
|
|
1877 an undefined effect.</P
|
|
|
1878 ><P
|
|
|
1879 >All numbers are in linking scripts are specified in hexadecimal. All directives
|
|
|
1880 are case sensitive although the hexadecimal numbers are not.</P
|
|
|
1881 ><P
|
|
|
1882 >A section name can be specified as a "*", then any section not
|
|
|
1883 already matched by the script will be matched. The "*" can be followed
|
|
|
1884 by a comma and a flag to narrow the section down slightly, also.
|
|
|
1885 If the flag is "!bss", then any section that is not flagged as a bss section
|
|
|
1886 will be matched. If the flag is "bss", then any section that is flagged as
|
|
|
1887 bss will be matched.</P
|
|
|
1888 ><P
|
|
|
1889 >The following directives are understood in a linker script.</P
|
|
|
1890 ><P
|
|
|
1891 ></P
|
|
|
1892 ><DIV
|
|
|
1893 CLASS="VARIABLELIST"
|
|
|
1894 ><DL
|
|
|
1895 ><DT
|
|
|
1896 >section <CODE
|
|
|
1897 CLASS="PARAMETER"
|
|
|
1898 >name</CODE
|
|
|
1899 > load <CODE
|
|
|
1900 CLASS="PARAMETER"
|
|
|
1901 >addr</CODE
|
|
|
1902 ></DT
|
|
|
1903 ><DD
|
|
|
1904 ><P
|
|
|
1905 > This causes the section <CODE
|
|
|
1906 CLASS="PARAMETER"
|
|
|
1907 >name</CODE
|
|
|
1908 > to load at
|
|
|
1909 <CODE
|
|
|
1910 CLASS="PARAMETER"
|
|
|
1911 >addr</CODE
|
|
|
1912 >. For the raw target, only one "load at" entry is
|
|
|
1913 allowed for non-bss sections and it must be the first one. For raw targets,
|
|
|
1914 it affects the addresses the linker assigns to symbols but has no other
|
|
|
1915 affect on the output. bss sections may all have separate load addresses but
|
|
|
1916 since they will not appear in the binary anyway, this is okay.</P
|
|
|
1917 ><P
|
|
|
1918 >For the decb target, each "load" entry will cause a new "block" to be
|
|
|
1919 output to the binary which will contain the load address. It is legal for
|
|
|
1920 sections to overlap in this manner - the linker assumes the loader will sort
|
|
|
1921 everything out.</P
|
|
|
1922 ></DD
|
|
|
1923 ><DT
|
|
|
1924 >section <CODE
|
|
|
1925 CLASS="PARAMETER"
|
|
|
1926 >name</CODE
|
|
|
1927 ></DT
|
|
|
1928 ><DD
|
|
|
1929 ><P
|
|
|
1930 > This will cause the section <CODE
|
|
|
1931 CLASS="PARAMETER"
|
|
|
1932 >name</CODE
|
|
|
1933 > to load after the previously listed
|
|
|
1934 section.</P
|
|
|
1935 ></DD
|
|
|
1936 ><DT
|
|
|
1937 >exec <CODE
|
|
|
1938 CLASS="PARAMETER"
|
|
|
1939 >addr or sym</CODE
|
|
|
1940 ></DT
|
|
|
1941 ><DD
|
|
|
1942 ><P
|
|
|
1943 >This will cause the execution address (entry point) to be the address
|
|
|
1944 specified (in hex) or the specified symbol name. The symbol name must
|
|
|
1945 match a symbol that is exported by one of the object files being linked.
|
|
|
1946 This has no effect for targets that do not encode the entry point into the
|
|
|
1947 resulting file. If not specified, the entry point is assumed to be address 0
|
|
|
1948 which is probably not what you want. The default link scripts for targets
|
|
|
1949 that support this directive automatically starts at the beginning of the
|
|
|
1950 first section (usually "init" or "code") that is emitted in the binary.</P
|
|
|
1951 ></DD
|
|
|
1952 ><DT
|
|
|
1953 >pad <CODE
|
|
|
1954 CLASS="PARAMETER"
|
|
|
1955 >size</CODE
|
|
|
1956 ></DT
|
|
|
1957 ><DD
|
|
|
1958 ><P
|
|
|
1959 >This will cause the output file to be padded with NUL bytes to be exactly
|
|
|
1960 <CODE
|
|
|
1961 CLASS="PARAMETER"
|
|
|
1962 >size</CODE
|
|
|
1963 > bytes in length. This only makes sense for a raw target.</P
|
|
|
1964 ></DD
|
|
|
1965 ></DL
|
|
|
1966 ></DIV
|
|
|
1967 ></DIV
|
|
|
1968 ></DIV
|
|
|
1969 ><DIV
|
|
|
1970 CLASS="CHAPTER"
|
|
|
1971 ><HR><H1
|
|
|
1972 ><A
|
|
|
1973 NAME="AEN639"
|
|
|
1974 ></A
|
|
|
1975 >Chapter 5. Libraries and LWAR</H1
|
|
|
1976 ><P
|
|
|
1977 >LWTOOLS also includes a tool for managing libraries. These are analogous to
|
|
|
1978 the static libraries created with the "ar" tool on POSIX systems. Each library
|
|
|
1979 file contains one or more object files. The linker will treat the object
|
|
|
1980 files within a library as though they had been specified individually on
|
|
|
1981 the command line except when resolving external references. External references
|
|
|
1982 are looked up first within the object files within the library and then, if
|
|
|
1983 not found, the usual lookup based on the order the files are specified on
|
|
|
1984 the command line occurs.</P
|
|
|
1985 ><P
|
|
|
1986 >The tool for creating these libary files is called LWAR.</P
|
|
|
1987 ><DIV
|
|
|
1988 CLASS="SECTION"
|
|
|
1989 ><HR><H2
|
|
|
1990 CLASS="SECTION"
|
|
|
1991 ><A
|
|
|
1992 NAME="AEN643"
|
|
|
1993 >5.1. Command Line Options</A
|
|
|
1994 ></H2
|
|
|
1995 ><P
|
|
|
1996 >The binary for LWAR is called "lwar". Note that the binary is in lower
|
|
|
1997 case. The options lwar understands are listed below. For archive manipulation
|
|
|
1998 options, the first non-option argument is the name of the archive. All other
|
|
|
1999 non-option arguments are the names of files to operate on.</P
|
|
|
2000 ><P
|
|
|
2001 ></P
|
|
|
2002 ><DIV
|
|
|
2003 CLASS="VARIABLELIST"
|
|
|
2004 ><DL
|
|
|
2005 ><DT
|
|
|
2006 ><CODE
|
|
|
2007 CLASS="OPTION"
|
|
|
2008 >--add</CODE
|
|
|
2009 >, <CODE
|
|
|
2010 CLASS="OPTION"
|
|
|
2011 >-a</CODE
|
|
|
2012 ></DT
|
|
|
2013 ><DD
|
|
|
2014 ><P
|
|
|
2015 >This option specifies that an archive is going to have files added to it.
|
|
|
2016 If the archive does not already exist, it is created. New files are added
|
|
|
2017 to the end of the archive.</P
|
|
|
2018 ></DD
|
|
|
2019 ><DT
|
|
|
2020 ><CODE
|
|
|
2021 CLASS="OPTION"
|
|
|
2022 >--create</CODE
|
|
|
2023 >, <CODE
|
|
|
2024 CLASS="OPTION"
|
|
|
2025 >-c</CODE
|
|
|
2026 ></DT
|
|
|
2027 ><DD
|
|
|
2028 ><P
|
|
|
2029 >This option specifies that an archive is going to be created and have files
|
|
|
2030 added to it. If the archive already exists, it is truncated.</P
|
|
|
2031 ></DD
|
|
|
2032 ><DT
|
|
|
2033 ><CODE
|
|
|
2034 CLASS="OPTION"
|
|
|
2035 >--merge</CODE
|
|
|
2036 >, <CODE
|
|
|
2037 CLASS="OPTION"
|
|
|
2038 >-m</CODE
|
|
|
2039 ></DT
|
|
|
2040 ><DD
|
|
|
2041 ><P
|
|
|
2042 >If specified, any files specified to be added to an archive will be checked
|
|
|
2043 to see if they are archives themselves. If so, their constituent members are
|
|
|
2044 added to the archive. This is useful for avoiding archives containing archives.</P
|
|
|
2045 ></DD
|
|
|
2046 ><DT
|
|
|
2047 ><CODE
|
|
|
2048 CLASS="OPTION"
|
|
|
2049 >--list</CODE
|
|
|
2050 >, <CODE
|
|
|
2051 CLASS="OPTION"
|
|
|
2052 >-l</CODE
|
|
|
2053 ></DT
|
|
|
2054 ><DD
|
|
|
2055 ><P
|
|
|
2056 >This will display a list of the files contained in the archive.</P
|
|
|
2057 ></DD
|
|
|
2058 ><DT
|
|
|
2059 ><CODE
|
|
|
2060 CLASS="OPTION"
|
|
|
2061 >--debug</CODE
|
|
|
2062 >, <CODE
|
|
|
2063 CLASS="OPTION"
|
|
|
2064 >-d</CODE
|
|
|
2065 ></DT
|
|
|
2066 ><DD
|
|
|
2067 ><P
|
|
|
2068 >This option increases the debugging level. It is only useful for LWTOOLS
|
|
|
2069 developers.</P
|
|
|
2070 ></DD
|
|
|
2071 ><DT
|
|
|
2072 ><CODE
|
|
|
2073 CLASS="OPTION"
|
|
|
2074 >--help</CODE
|
|
|
2075 >, <CODE
|
|
|
2076 CLASS="OPTION"
|
|
|
2077 >-?</CODE
|
|
|
2078 ></DT
|
|
|
2079 ><DD
|
|
|
2080 ><P
|
|
|
2081 >This provides a listing of command line options and a brief description
|
|
|
2082 of each.</P
|
|
|
2083 ></DD
|
|
|
2084 ><DT
|
|
|
2085 ><CODE
|
|
|
2086 CLASS="OPTION"
|
|
|
2087 >--usage</CODE
|
|
|
2088 ></DT
|
|
|
2089 ><DD
|
|
|
2090 ><P
|
|
|
2091 >This will display a usage summary.
|
|
|
2092 of each.</P
|
|
|
2093 ></DD
|
|
|
2094 ><DT
|
|
|
2095 ><CODE
|
|
|
2096 CLASS="OPTION"
|
|
|
2097 >--version</CODE
|
|
|
2098 >, <CODE
|
|
|
2099 CLASS="OPTION"
|
|
|
2100 >-V</CODE
|
|
|
2101 ></DT
|
|
|
2102 ><DD
|
|
|
2103 ><P
|
|
|
2104 >This will display the version of LWLINK.
|
|
|
2105 of each.</P
|
|
|
2106 ></DD
|
|
|
2107 ></DL
|
|
|
2108 ></DIV
|
|
|
2109 ></DIV
|
|
|
2110 ></DIV
|
|
|
2111 ><DIV
|
|
|
2112 CLASS="CHAPTER"
|
|
|
2113 ><HR><H1
|
|
|
2114 ><A
|
|
|
2115 NAME="OBJCHAP"
|
|
|
2116 ></A
|
|
|
2117 >Chapter 6. Object Files</H1
|
|
|
2118 ><P
|
|
|
2119 >LWTOOLS uses a proprietary object file format. It is proprietary in the sense
|
|
|
2120 that it is specific to LWTOOLS, not that it is a hidden format. It would be
|
|
|
2121 hard to keep it hidden in an open source tool chain anyway. This chapter
|
|
|
2122 documents the object file format.</P
|
|
|
2123 ><P
|
|
|
2124 >An object file consists of a series of sections each of which contains a
|
|
|
2125 list of exported symbols, a list of incomplete references, and a list of
|
|
|
2126 "local" symbols which may be used in calculating incomplete references. Each
|
|
|
2127 section will obviously also contain the object code.</P
|
|
|
2128 ><P
|
|
|
2129 >Exported symbols must be completely resolved to an address within the
|
|
|
2130 section it is exported from. That is, an exported symbol must be a constant
|
|
|
2131 rather than defined in terms of other symbols.</P
|
|
|
2132 ><P
|
|
|
2133 >Each object file starts with a magic number and version number. The magic
|
|
|
2134 number is the string "LWOBJ16" for this 16 bit object file format. The only
|
|
|
2135 defined version number is currently 0. Thus, the first 8 bytes of the object
|
|
|
2136 file are <FONT
|
|
|
2137 COLOR="RED"
|
|
|
2138 >4C574F424A313600</FONT
|
|
|
2139 ></P
|
|
|
2140 ><P
|
|
|
2141 >Each section has the following items in order:</P
|
|
|
2142 ><P
|
|
|
2143 ></P
|
|
|
2144 ><UL
|
|
|
2145 ><LI
|
|
|
2146 ><P
|
|
|
2147 >section name</P
|
|
|
2148 ></LI
|
|
|
2149 ><LI
|
|
|
2150 ><P
|
|
|
2151 >flags</P
|
|
|
2152 ></LI
|
|
|
2153 ><LI
|
|
|
2154 ><P
|
|
|
2155 >list of local symbols (and addresses within the section)</P
|
|
|
2156 ></LI
|
|
|
2157 ><LI
|
|
|
2158 ><P
|
|
|
2159 >list of exported symbols (and addresses within the section)</P
|
|
|
2160 ></LI
|
|
|
2161 ><LI
|
|
|
2162 ><P
|
|
|
2163 >list of incomplete references along with the expressions to calculate them</P
|
|
|
2164 ></LI
|
|
|
2165 ><LI
|
|
|
2166 ><P
|
|
|
2167 >the actual object code (for non-BSS sections)</P
|
|
|
2168 ></LI
|
|
|
2169 ></UL
|
|
|
2170 ><P
|
|
|
2171 >The section starts with the name of the section with a NUL termination
|
|
|
2172 followed by a series of flag bytes terminated by NUL. There are only two
|
|
|
2173 flag bytes defined. A NUL (0) indicates no more flags and a value of 1
|
|
|
2174 indicates the section is a BSS section. For a BSS section, no actual
|
|
|
2175 code is included in the object file.</P
|
|
|
2176 ><P
|
|
|
2177 >Either a NULL section name or end of file indicate the presence of no more
|
|
|
2178 sections.</P
|
|
|
2179 ><P
|
|
|
2180 >Each entry in the exported and local symbols table consists of the symbol
|
|
|
2181 (NUL terminated) followed by two bytes which contain the value in big endian
|
|
|
2182 order. The end of a symbol table is indicated by a NULL symbol name.</P
|
|
|
2183 ><P
|
|
|
2184 >Each entry in the incomplete references table consists of an expression
|
|
|
2185 followed by a 16 bit offset where the reference goes. Expressions are
|
|
|
2186 defined as a series of terms up to an "end of expression" term. Each term
|
|
|
2187 consists of a single byte which identifies the type of term (see below)
|
|
|
2188 followed by any data required by the term. Then end of the list is flagged
|
|
|
2189 by a NULL expression (only an end of expression term).</P
|
|
|
2190 ><DIV
|
|
|
2191 CLASS="TABLE"
|
|
|
2192 ><A
|
|
|
2193 NAME="AEN726"
|
|
|
2194 ></A
|
|
|
2195 ><P
|
|
|
2196 ><B
|
|
|
2197 >Table 6-1. Object File Term Types</B
|
|
|
2198 ></P
|
|
|
2199 ><TABLE
|
|
|
2200 BORDER="1"
|
|
|
2201 FRAME="border"
|
|
|
2202 CLASS="CALSTABLE"
|
|
|
2203 ><COL><COL><THEAD
|
|
|
2204 ><TR
|
|
|
2205 ><TH
|
|
|
2206 >TERMTYPE</TH
|
|
|
2207 ><TH
|
|
|
2208 >Meaning</TH
|
|
|
2209 ></TR
|
|
|
2210 ></THEAD
|
|
|
2211 ><TBODY
|
|
|
2212 ><TR
|
|
|
2213 ><TD
|
|
|
2214 >00</TD
|
|
|
2215 ><TD
|
|
|
2216 >end of expression</TD
|
|
|
2217 ></TR
|
|
|
2218 ><TR
|
|
|
2219 ><TD
|
|
|
2220 >01</TD
|
|
|
2221 ><TD
|
|
|
2222 >integer (16 bit in big endian order follows)</TD
|
|
|
2223 ></TR
|
|
|
2224 ><TR
|
|
|
2225 ><TD
|
|
|
2226 >02</TD
|
|
|
2227 ><TD
|
|
|
2228 > external symbol reference (NUL terminated symbol name follows)</TD
|
|
|
2229 ></TR
|
|
|
2230 ><TR
|
|
|
2231 ><TD
|
|
|
2232 >03</TD
|
|
|
2233 ><TD
|
|
|
2234 >local symbol reference (NUL terminated symbol name follows)</TD
|
|
|
2235 ></TR
|
|
|
2236 ><TR
|
|
|
2237 ><TD
|
|
|
2238 >04</TD
|
|
|
2239 ><TD
|
|
|
2240 >operator (1 byte operator number)</TD
|
|
|
2241 ></TR
|
|
|
2242 ><TR
|
|
|
2243 ><TD
|
|
|
2244 >05</TD
|
|
|
2245 ><TD
|
|
|
2246 >section base address reference</TD
|
|
|
2247 ></TR
|
|
|
2248 ></TBODY
|
|
|
2249 ></TABLE
|
|
|
2250 ></DIV
|
|
|
2251 ><P
|
|
|
2252 >External references are resolved using other object files while local
|
|
|
2253 references are resolved using the local symbol table(s) from this file. This
|
|
|
2254 allows local symbols that are not exported to have the same names as
|
|
|
2255 exported symbols or external references.</P
|
|
|
2256 ><DIV
|
|
|
2257 CLASS="TABLE"
|
|
|
2258 ><A
|
|
|
2259 NAME="AEN753"
|
|
|
2260 ></A
|
|
|
2261 ><P
|
|
|
2262 ><B
|
|
|
2263 >Table 6-2. Object File Operator Numbers</B
|
|
|
2264 ></P
|
|
|
2265 ><TABLE
|
|
|
2266 BORDER="1"
|
|
|
2267 FRAME="border"
|
|
|
2268 CLASS="CALSTABLE"
|
|
|
2269 ><COL><COL><THEAD
|
|
|
2270 ><TR
|
|
|
2271 ><TH
|
|
|
2272 >Number</TH
|
|
|
2273 ><TH
|
|
|
2274 >Operator</TH
|
|
|
2275 ></TR
|
|
|
2276 ></THEAD
|
|
|
2277 ><TBODY
|
|
|
2278 ><TR
|
|
|
2279 ><TD
|
|
|
2280 >01</TD
|
|
|
2281 ><TD
|
|
|
2282 >addition (+)</TD
|
|
|
2283 ></TR
|
|
|
2284 ><TR
|
|
|
2285 ><TD
|
|
|
2286 >02</TD
|
|
|
2287 ><TD
|
|
|
2288 >subtraction (-)</TD
|
|
|
2289 ></TR
|
|
|
2290 ><TR
|
|
|
2291 ><TD
|
|
|
2292 >03</TD
|
|
|
2293 ><TD
|
|
|
2294 >multiplication (*)</TD
|
|
|
2295 ></TR
|
|
|
2296 ><TR
|
|
|
2297 ><TD
|
|
|
2298 >04</TD
|
|
|
2299 ><TD
|
|
|
2300 >division (/)</TD
|
|
|
2301 ></TR
|
|
|
2302 ><TR
|
|
|
2303 ><TD
|
|
|
2304 >05</TD
|
|
|
2305 ><TD
|
|
|
2306 >modulus (%)</TD
|
|
|
2307 ></TR
|
|
|
2308 ><TR
|
|
|
2309 ><TD
|
|
|
2310 >06</TD
|
|
|
2311 ><TD
|
|
|
2312 >integer division (\) (same as division)</TD
|
|
|
2313 ></TR
|
|
|
2314 ><TR
|
|
|
2315 ><TD
|
|
|
2316 >07</TD
|
|
|
2317 ><TD
|
|
|
2318 >bitwise and</TD
|
|
|
2319 ></TR
|
|
|
2320 ><TR
|
|
|
2321 ><TD
|
|
|
2322 >08</TD
|
|
|
2323 ><TD
|
|
|
2324 >bitwise or</TD
|
|
|
2325 ></TR
|
|
|
2326 ><TR
|
|
|
2327 ><TD
|
|
|
2328 >09</TD
|
|
|
2329 ><TD
|
|
|
2330 >bitwise xor</TD
|
|
|
2331 ></TR
|
|
|
2332 ><TR
|
|
|
2333 ><TD
|
|
|
2334 >0A</TD
|
|
|
2335 ><TD
|
|
|
2336 >boolean and</TD
|
|
|
2337 ></TR
|
|
|
2338 ><TR
|
|
|
2339 ><TD
|
|
|
2340 >0B</TD
|
|
|
2341 ><TD
|
|
|
2342 >boolean or</TD
|
|
|
2343 ></TR
|
|
|
2344 ><TR
|
|
|
2345 ><TD
|
|
|
2346 >0C</TD
|
|
|
2347 ><TD
|
|
|
2348 >unary negation, 2's complement (-)</TD
|
|
|
2349 ></TR
|
|
|
2350 ><TR
|
|
|
2351 ><TD
|
|
|
2352 >0D</TD
|
|
|
2353 ><TD
|
|
|
2354 >unary 1's complement (^)</TD
|
|
|
2355 ></TR
|
|
|
2356 ></TBODY
|
|
|
2357 ></TABLE
|
|
|
2358 ></DIV
|
|
|
2359 ><P
|
|
|
2360 >An expression is represented in a postfix manner with both operands for
|
|
|
2361 binary operators preceding the operator and the single operand for unary
|
|
|
2362 operators preceding the operator.</P
|
|
|
2363 ></DIV
|
|
|
2364 ></DIV
|
|
|
2365 ></BODY
|
|
|
2366 ></HTML
|
|
|
2367 > |
