Hi, Pit:
Unfortunately, the syntax for macros in the Motorola assemblers have never been very symbolic in the eight-bit world. The rules for macros go something like this:
Symbolic names for macro parameters are not supported. The "MACRO" keyword cannot be followed by arguments.
In the macro body, the first parameter is specified as "\1", the second as "\2", etcetera. If more than 9 parameters are needed, then the tenth parameter is specified as "\A", the eleventh as "\B", etcetera. No more than 35 parameters are allowed.
Macro arguments must be separated by commas. A space will terminate the argument list. A null argument is specified by two commas in a row, with no space in between.
There is also a "\0" parameter, which is used to specify the character that might follow a "." (period) at the end the macro name in its invocation. As an example, if a macro named "Alban" was invoked as "Alban.b", parameter \0 would be equal to "b".
hope that helps.