ASSEMBLER/DISASSEMBLER
M68CPU32BUG/D 4-2
4.1.2 M68300 Family Resident Structured Assembler Comparison
There are several major differences between the CPU32Bug assembler and the M68300 Family
resident structured assembler. The resident assembler is a two-pass assembler that processes an
entire program as a unit, while the CPU32Bug assembler processes each line of a program as an
individual unit. Due mainly to this basic functional difference, the CPU32Bug assembler
capabilities are more restricted:
•
Label and line numbers are not used. Labels are used to reference other lines and
locations in a program. The one-line assembler has no knowledge of other lines and,
therefore, cannot make the required association between a label and the label
definition located on a separate line.
•
Source lines are not saved. In order to read back a program after it is entered, the
machine code is disassembled and then displayed as mnemonics and operands.
•
Only two directives (DC.W and SYSCALL) are accepted.
•
No macro operation capability is included.
•
No conditional assembly is used.
•
No structured assembly is used.
•
Several symbols recognized by the resident assembler are not included in the
CPU32Bug assembler character set. These symbols include ’’>’’ and ’’<’’. Three other
symbols have multiple meaning to the resident assembler, depending on the context.
These are:
Asterisk (*) - Multiply or current PC
Slash (/) - Divide or delimiter in a register list
Ampersand (&) - And or decimal number prefix
Although functional differences exist between the two assemblers, the one-line assembler is a
true subset of the resident assembler. The CPU32Bug assembler format and syntax are acceptable
to the resident assembler except as described above.
4.2 SOURCE PROGRAM CODING
A source program is a sequence of source statements arranged in a logical manner to perform
predetermined tasks. Each source statement occupies a line and must be either an executable
instruction, a DC.W directive, or a SYSCALL assembler directive. Each source statement
follows a consistent source line format.
Содержание M68CPU32BUG
Страница 16: ...GENERAL INFORMATION M68CPU32BUG D REV 1 1 8 ...
Страница 30: ...DEBUG MONITOR DESCRIPTION M68CPU32BUG D REV 1 2 14 ...
Страница 102: ...DEBUG MONITOR COMMANDS M68CPU32BUG D REV 1 3 72 ...
Страница 168: ...DIAGNOSTIC FIRMWARE GUIDE M68CPU32BUG D REV 1 6 24 ...