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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 DEFL 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 MEX ORG 6000H* This is the macro definition:macxampl MACR LD \0,$60 LD \1,$52\.0 ADD \0,\1 JR NZ,\.0 ENDM* This is the macro call: macxampl A,B
And now the listing generated during assembly: 1 NAM MACXAMPL 2 TTL *** Dummy Labels *** 3 LIST 4 SYM 5 MEX 6 6000 ORG 6000H 7 8 * This is the macro definition: 9 10 macxampl MACR 11 LD \0,$60 12 LD \1,$52 13 \.0 ADD \0,\1 14 JR NZ,\.0 15 ENDM 16 17 * This is the macro call: 18 19 macxampl A,B 6000 3E 60 LD A,$60 6002 06 52 LD B,$52 6004 80 .00000 ADD A,B 6005 20 FD JR NZ,.00000 20 21Assembly completeBytes filed: 70 errors0 warningsSymbol table:.00000 6004 1 symbols.