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CROSS ASSEMBLER->Assembler Macros->Dummy Labels
If you include an ordinary label in the macro definition then, except where it is being defined using the SET directive, it will only be possible to call that macro once. A second call will generate a duplicate label error. Dummy labels overcome this problem. Dummy labels are \.0 to \.9 and \.A to \.Z (or \.a to \.z since the dummy labels are case insensitive). These symbols are used within the macro definition in place of ordinary labels, and when the macro is expanded the assembler replaces them with labels .00000, .00001, .00002 etc. Unique labels are therefore generated each time the macro is called.
The following example illustrates the use of dummy labels.
Firstly the source code listing:
NAM MACXAMPL TTL *** Dummy Labels *** LIST SYM ORG 6000H* This is the macro definition:macxampl MACR MOVE $6000,\0 MOVE $52,\1\.0 ADD \1,\0 DBEQ \0,\.0 ENDM* This is the macro call:macxampl D1,D2
And now the listing generated during assembly: 1 NAM MACXAMPL 2 TTL *** Dummy Labels *** 3 LIST 4 00000000 SYM 500006000 ORG 6000H 6 7 * This is the macro definition: 8 9 macxampl MACR 10 MOVE $6000,\0 11 MOVE $52,\1 12 \.0 ADD \1,\0 13 DBEQ \0,\.0 14 ENDM 15 16 * This is the macro call: 17 18 macxampl D1,D2 00006000 32386000 MOVE $6000,D1 00006004 34380052 MOVE $52,D2 00006008 D242 .00000 ADD D2,D1 0000600A 57C9FFFC DBEQ D1,.00000 19Assembly completeBytes filed: 140 errors0 warningsSymbol table:.00000 00006008 1 symbols.