Quick reference guide monitor

A ASCII Dump. Two args: <start address> and <end address>. Works in page mode of 256 bytes. Enter for next page, ESC to abort.
B Dump one I/O port. real-time Two arguments: <port address> and <repeat rate>
C Compare memory. Three arguments <start address>, <end address> and <other start address>. ESC to abort
D Debugger. Two arguments. <start address> and <end address>
E Edit. Inspect and edit memory locations. One argument the <address>. Use Enter for next address, ESC to abort.
F Fill. Three args: <start address>, <end address>, <value>
G Go. One argument, the <address> to jump to.
H Hex/ASCII dump. Two arguments, <start address> and <end address>. Memory is dumped in 256 byte chunks. Enter for next page, ESC to abort.
J I/O register dump. Dumps $BB00 - $BFFF for BEM-3, $BE00 - $BFFF for BEM-4.
K Dump one page. One argument <start address>.
L Load S19 file. No arguments, goes directly into load mode. On receiving a end record, it returns to the monitor. Reset to abort.
M Move. Three args: <start address>, <end address>, <target address>
N Debugger. One argument: the <start address>. One instruction at a time. Enter for next instruction, ESC for same instruction again. 'Q' for return to monitor.
O Memory Map. Prints memory in 256 chunks. Chunks with the same value for all addresses prints that value, 'xx' otherwise.
P Print registers. No argument.
Q Go to user program (warm start). No argument.
R Run from last executed address. No arguments, executes immediately
S Save S19 file. Two arguments, start and end end address.
V Verify. No arguments, goes directly into verify mode. This is very similar to the Load command, but instead of writing to memory, the values are compared. This can be used as basic RAM-test.
X Go to user vector. No argument.
Z Go to address of last executed Go. No argument.
/ Clear screen. No argument.
? Help. No argument.

Edit memory command subcommands

<ESC> End. Return to monitor
~
Soft escape (return to caller)
<ENTE>> Next address
<Space> Previous address
S Enter string (max 64)
' Enter ASCII
% Inspect and enter binary
0-9A-F Edit value
R Calculate 8 bits offset
L Calculate 16 bits offset

Quick reference guide debugger

<Enter> Next instruction
Q Quit
A Modify A register
B Modify B register
C Modify CC register
D Modify direct page
G Print a string?
H Hexdump from monitor
M Modify memory
P Modify PC
S ?
X Modify X register
Y Modify Y register

Last updated: 2026-10-14

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