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Using SCM

Phillip Stevens edited this page Jan 12, 2020 · 3 revisions

The Small Computer Monitor is a classic machine code monitor for Z80/Z180 based systems. It was written by Stephen Cousins.

It supports RC2014 systems, and is supported by the Z88DK.

Full documentation on the SCM is available from here.

As an introduction typing a ? or HELP will bring up the help screen, which shows the commands available

*?
Small Computer Monitor by Stephen C Cousins (www.scc.me.uk)
Version 1.0.0 configuration R1 for Z80 based RC2014 systems

Monitor commands:
A [<address>] = Assemble | D [<address>] = Disassemble
M [<address>] = Memory display | E [<address>] = Edit memory
R [<name>] = Registers/edit | F [<name>] = Flags/edit
B [<address>] = Breakpoint | S [<address>] = Single step
I <port> = Input from port | O <port> <data> = Output to port
G [<address>] = Go to program
BAUD <device> <rate> | CONSOLE <device>
FILL <start> <end> <byte> | API <function> [<A>] [<DE>]
DEVICES, DIR, HELP, RESET

A 2nd variation has the ROM designation “88” and is a 16k ROM for use on the RC2014 Pro. This works exactly the same as the “9”, but includes a BASIC and CP/M loader;

*?
Small Computer Monitor by Stephen C Cousins (www.scc.me.uk)
Version 1.0.0 configuration R4 for Z80 based RC2014 systems

Monitor commands:
A [<address>] = Assemble | D [<address>] = Disassemble
M [<address>] = Memory display | E [<address>] = Edit memory
R [<name>] = Registers/edit | F [<name>] = Flags/edit
B [<address>] = Breakpoint | S [<address>] = Single step
I <port> = Input from port | O <port> <data> = Output to port
G [<address>] = Go to program
BAUD <device> <rate> | CONSOLE <device>
FILL <start> <end> <byte> | API <function> [<A>] [<DE>]
DEVICES, DIR, HELP, RESET
BASIC Grant Searle’s adaptation of Microsoft BASIC
WBASIC Warm start BASIC (retains BASIC program)
CPM Load CP/M from Compact Flash (requires prepared CF card)
*CPM

Z80 CP/M BIOS 1.0 by G. Searle 2007-13

CP/M 2.2 Copyright 1979 (c) by Digital Research

A>

Typing BASIC, WBASIC or CPM at the prompt will boot in to the appropriate operating system as shown above.

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