User`s manual

OPERATING INSTRUCTIONS
M68332BCC/D 3-6 MOTOROLA
REV 1
3.4 MONITOR DESCRIPTION
CPU32Bug performs various operations in response to user commands entered at the keyboard.
When the debugger prompt CPU32Bug> appears on the terminal screen, the debugger is ready
to accept commands.
As the command line is entered it is stored in an internal buffer. Execution begins only after the
carriage return is entered. This lets the user correct entry errors using the control characters
described in the M68CPU32BUG Debug Monitor User’s Manual, M68CPU32BUG/AD1.
After the debugger executes a command it returns with the CPU32Bug> prompt. However, if the
entered command causes execution of user target code, (i.e., GO), then control may or may not
return to the debugger. This depends on the user program function. For example, if a breakpoint
is specified, control returns to the debugger when the breakpoint is encountered during user
program execution. The user program also returns control to the debugger by means of the TRAP
#15 system call function, .RETURN.
Included as part of the CPU32Bug firmware is a single-line assembler/disassembler function.
The assembler is an interactive assembler/editor in which source programs are not saved. Each
source line is translated into MC68332 MCU machine language code and stored line-by-line into
memory as it is entered. In order to display an instruction, the machine code is disassembled and
the instruction mnemonic and operands are displayed. All valid MC68332 MCU instructions are
supported.
The CPU32Bug assembler is effectively a subset of the M68000 Family Structured Assembler
(M68MASM). It has some limitations as compared with the M68MASM assembler, such as not
allowing line numbers and labels; however, it is a useful tool for creating, modifying, and
debugging MC68332 MCU code.