Commodore 128D - Page 383

APPENDIX J
MACHINE
LANGUAGE
MONITOR
Introduction
Commodore 128 has a built-in machine language monitor program
which lets the user write and examine machine language programs
easily. Commodore 128 MONITOR includes a machine language
monitor, a mini-assembler and a disassembler. The built-in monitor
works only in C128 mode; either 40 column or 80 column.
Machine language programs written using Commodore 128 MONI
TOR can run by themselves or be used as very fast subroutines for
BASIC programs since the Commodore 128 MONITOR has the abil
ity to coexist peacefully with BASIC.
Care must be taken to position the assembly language programs in
memory so the BASIC program does not overwrite them.
To enter the monitor from BASIC, type:
MONITOR!
Summary of Commodore 128 Monitor Commands
FORMAT
<start_address> <opcode) [operand]
dress)
[<start_address) <end_address]]
<start_address) <endaddress> <byte)
[address]
<start_address) <end_address) <byte1)
[<byte_n)...]
<start_address) <end_address> *<asciLstring>
[address]
"(filename)" [,<device_#> [,<loacLaddress)]]
[)startaddress) [encLaddress]]
"<filename)",<device_#>,<starLaddress) <ia
Laddress +1)
(starLaddress) <encLaddress) <to_start_ad-
dress)
"(filename)" [,<device_#) [,<loacLaddress)]]
KEYWORD
ASSEMBLE
COMPARE
DISASSEMBLE
FILL
GO
HUNT
GOSUB
LOAD
MEMORY
REGISTERS
SAVE
TRANSFER
VERIFY
EXIT
(period)
(greater than)
(semicolon)
(at sign)
FUNCTION
Assembles a line of 8502 code
Compares two sections of memory and reports
differences
Disassembles a line or lines of 8502 code
Fills a range of memory with the specified byte
Starts execution at the specified address
Hunts through memory within a specified range
for all occurrences of a set of bytes
Jumps to the subroutine
Loads a file from tape or disk
Displays the hexadecimal values of memory
locations
Displays the 8502 registers
Saves to tape or disk
Transfers code from one section of memory to
another
Compares memory.with tape or disk
Exits Commodore 128 MONITOR
Assembles a line of 8502 code
Modifies memory
Modifies 8502 register displays
Displays disk status, sends disk command, dis
plays directory
disk status
disk command
disk catalog
A
C
D
F
G
H
H
J
L
M
R
c
o
T
|
V
X
>
@
@[device_#]
@[device_#I,<command_string)]
@[device_#],$[[<drive)][:<file_spec)]]
NOTES: < > enclose required parameters.
[ ] enclose optional parameters.
NOTE: See important 5-digit Address note on the next page.
379 APPENDIX J—Machine Language Monitor