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Add support for 6800 compatibility instructions. The occasional program uses the 6800 compatibility instructions since they are actually specified by Motorola in at least some documentation. They advertised the 6809 as source compatible with the 6800. This mode is not enabled by default, however. It is my belief that receiving an error when using a non-6809 instruction is more useful since it is unlikely that much 6800 source code is being assembled for the 6809 these days. Nevertheless, the --6809compat option is present for just those purposes so one does not have to resort to using macros (which would work equally well in most cases).
author William Astle <lost@l-w.ca>
date Tue, 15 Apr 2014 10:57:34 -0600
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332:26bfe8d557e2 333:507f442dc71e
1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN""http://www.w3.org/TR/html4/loose.dtd">
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77 >3.4. Symbols</A
78 ></H1
79 ><P
80 >Symbols have no length restriction. They may contain letters, numbers, dots,
81 dollar signs, and underscores. They must start with a letter, dot, or
82 underscore.</P
83 ><P
84 >LWASM also supports the concept of a local symbol. A local symbol is one
85 which contains either a "?" or a "@", which can appear anywhere in the symbol.
86 The scope of a local symbol is determined by a number of factors. First,
87 each included file gets its own local symbol scope. A blank line will also
88 be considered a local scope barrier. Macros each have their own local symbol
89 scope as well (which has a side effect that you cannot use a local symbol
90 as an argument to a macro). There are other factors as well. In general,
91 a local symbol is restricted to the block of code it is defined within.</P
92 ><P
93 >By default, unless assembling to the os9 target, a "$" in the symbol will
94 also make it local. This can be controlled by the "dollarlocal" and
95 "nodollarlocal" pragmas. In the absence of a pragma to the contrary, for
96 the os9 target, a "$" in the symbol will not make it considered local while
97 for all other targets it will.</P
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