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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 >Object Files</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"><LINK
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9 REL="HOME"
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10 TITLE="LW Tool Chain"
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11 HREF="index.html"><LINK
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12 REL="UP"
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13 TITLE="Output Formats"
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14 HREF="c18.html"><LINK
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15 REL="PREVIOUS"
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16 TITLE="OS9 Modules"
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17 HREF="x29.html"><LINK
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18 REL="NEXT"
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19 TITLE="LWASM"
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20 HREF="c43.html"></HEAD
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21 ><BODY
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22 CLASS="SECTION"
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23 BGCOLOR="#FFFFFF"
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24 TEXT="#000000"
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25 LINK="#0000FF"
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26 VLINK="#840084"
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27 ALINK="#0000FF"
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28 ><DIV
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29 CLASS="NAVHEADER"
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30 ><TABLE
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31 SUMMARY="Header navigation table"
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32 WIDTH="100%"
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33 BORDER="0"
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34 CELLPADDING="0"
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35 CELLSPACING="0"
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36 ><TR
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37 ><TH
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38 COLSPAN="3"
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39 ALIGN="center"
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40 >LW Tool Chain</TH
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41 ></TR
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42 ><TR
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43 ><TD
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44 WIDTH="10%"
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45 ALIGN="left"
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46 VALIGN="bottom"
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47 ><A
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48 HREF="x29.html"
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49 ACCESSKEY="P"
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50 >Prev</A
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51 ></TD
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52 ><TD
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53 WIDTH="80%"
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54 ALIGN="center"
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55 VALIGN="bottom"
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56 >Chapter 2. Output Formats</TD
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57 ><TD
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58 WIDTH="10%"
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59 ALIGN="right"
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60 VALIGN="bottom"
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61 ><A
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62 HREF="c43.html"
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63 ACCESSKEY="N"
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64 >Next</A
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65 ></TD
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66 ></TR
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67 ></TABLE
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68 ><HR
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69 ALIGN="LEFT"
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70 WIDTH="100%"></DIV
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71 ><DIV
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72 CLASS="SECTION"
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73 ><H1
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74 CLASS="SECTION"
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75 ><A
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76 NAME="AEN35"
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77 >2.4. Object Files</A
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78 ></H1
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79 ><P
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80 >LWASM supports generating a proprietary object file format which is
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81 described in <A
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82 HREF="c817.html"
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83 >Chapter 6</A
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84 >. LWLINK is then used to link these
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85 object files into a final binary in any of LWLINK's supported binary
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86 formats.</P
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87 ><P
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88 >Object files also support the concept of sections which are not valid
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89 for other output types. This allows related code from each object file
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90 linked to be collapsed together in the final binary.</P
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91 ><P
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92 >Object files are very flexible in that they allow references that are not
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93 known at assembly time to be resolved at link time. However, because the
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94 addresses of such references are not known at assembly time, there is no way
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95 for the assembler to deduce that an eight bit addressing mode is possible.
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96 That means the assember will default to using sixteen bit addressing
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97 whenever an external or cross-section reference is used.</P
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98 ><P
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99 >As of LWASM 2.4, it is possible to force direct page addressing for an
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100 external reference. Care must be taken to ensure the resulting addresses
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101 are really in the direct page since the linker does not know what the direct
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102 page is supposed to be and does not emit errors for byte overflows.</P
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103 ><P
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104 >It is also possible to use external references in an eight bit immediate
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105 mode instruction. In this case, only the low order eight bits will be used.
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106 Again, no byte overflows will be flagged.</P
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107 ></DIV
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108 ><DIV
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109 CLASS="NAVFOOTER"
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110 ><HR
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111 ALIGN="LEFT"
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112 WIDTH="100%"><TABLE
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113 SUMMARY="Footer navigation table"
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114 WIDTH="100%"
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115 BORDER="0"
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116 CELLPADDING="0"
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117 CELLSPACING="0"
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118 ><TR
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119 ><TD
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120 WIDTH="33%"
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121 ALIGN="left"
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122 VALIGN="top"
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123 ><A
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124 HREF="x29.html"
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125 ACCESSKEY="P"
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126 >Prev</A
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127 ></TD
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128 ><TD
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129 WIDTH="34%"
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130 ALIGN="center"
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131 VALIGN="top"
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132 ><A
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133 HREF="index.html"
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134 ACCESSKEY="H"
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135 >Home</A
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136 ></TD
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137 ><TD
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138 WIDTH="33%"
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139 ALIGN="right"
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140 VALIGN="top"
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141 ><A
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142 HREF="c43.html"
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143 ACCESSKEY="N"
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144 >Next</A
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145 ></TD
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146 ></TR
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147 ><TR
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148 ><TD
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149 WIDTH="33%"
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150 ALIGN="left"
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151 VALIGN="top"
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152 >OS9 Modules</TD
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153 ><TD
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154 WIDTH="34%"
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155 ALIGN="center"
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156 VALIGN="top"
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157 ><A
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158 HREF="c18.html"
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159 ACCESSKEY="U"
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160 >Up</A
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161 ></TD
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162 ><TD
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163 WIDTH="33%"
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164 ALIGN="right"
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165 VALIGN="top"
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166 >LWASM</TD
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167 ></TR
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168 ></TABLE
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169 ></DIV
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170 ></BODY
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171 ></HTML
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172 > |
