Zilog Z8F0130 - Manual (Page 340)

Using the Macro Assembler UM013037-1212
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Zilog Developer Studio II – Z8 Encore!
User Manual
.UNION Directive
The .UNION directive is similar to the .STRUCT directive, except that the offset is reset to
zero on each label. A .UNION directive cannot have an offset or parent union. The key-
word to terminate a .UNION definition is .ENDSTRUCT .
The .UNION directive has the following form:
[stag] .UNION
[name_1] DS count1
[name_2] DS count2
[tname] .TAG stagx [count]
...
[name_n] DS count3
[ssize] .ENDSTRUCT [stag]
An example of the .UNION directive usage is as follows:
BYTES .STRUCT

B0 DS 1

B1 DS 1

B2 DS 1

B3 DS 1

BSIZE .ENDSTRUCT BYTES
LONGBYTES .UNION

LDATA BLKL 1

BDATA .TAG BYTES

LSIZE .ENDSTRUCT LONGBYTES
.WITH and .ENDWITH Directives
Using the fully qualified names for fields within a structure can result in very long names.
The
.WITH directive allows the initial part of the name to be dropped.
The .WITH and .ENDWITH directives have the following form:
.WITH name
; directives
.ENDWITH [name]
The identifier name may be the name of a previously defined .STRUCT or .UNION , or an
ordinary label to which a structure has been attached using a .TAG directive. It can also be
the name of an equate or label with no structure attached. Within the .WITH section, the
assembler attempts to prepend “name.” to each identifier encountered, and selects the