EXMON II

(C) 1990 Beebug

An updated version of EXMON II, with updates and code comments from https://github.com/mincebert and https://github.com/tom-seddon. Based on BBC Micro EXMON II version 2.02.

Additional features:

• doesn't print EXMON II when you press BREAK

• now includes a properly Electron-compatible version

More to come. Watch this space!

Instructions

See EXMONIImanual.pdf in the repo.

Electron-specific instructions

The manual refers to an Electron version of EXMON II, but there don't seem to be any copies available. Perhaps it was planned, then never released; perhaps it's simply been lost to time.

The manual's Electron notes do largely apply to this version. Please also note the following:

• the ROM reports itself as EXMON IIe rather than EXMON II

• when using the editor, press FUNC+SHIFT+up/down to scroll to the next half page

• use ; to toggle between hex view and disassembly

• the dual screen commands have been removed - but much of the code remains, so problems are possible...

Building

Prerequisites

Windows

• Python 3.x

Additional dependencies are provided as pre-built EXEs in the repo.

POSIX-type

• GNU Make (make)
• Python 3.x (/usr/bin/python3)
• 64tass (64tass) - version 2974 works

Clone the repo

The repo has submodules. Clone it with --recursive:

git clone --recursive https://github.com/tom-seddon/exmon2_disassembly

Alternatively, if you already cloned it non-recursively, you can do the following from inside the working copy:

git submodule init
git submodule update

Build the code

Run make in the root of the working copy. (A make.bat is supplied for Windows, which will run the supplied copy of GNU Make.)

The output ROM images are in the .build folder in the working copy:

• exmon2.rom is for the BBC B/B+/Master
• exmon2e.rom is for the Electron

Using the ROMs on your BBC or emulator

The .rom files are ordinary 16 KB ROM images. Transfer them to your BBC, use them to program a PROM, load them into an emulator.

If you use BeebLink, add beeb in the working copy to your BeebLink search path. You'll get a volume called exmon2_build containing :Z.R.EXMON2 (BBC B/B+/Master version) and :Z.R.EXMON2E (Electron version).

Building an original copy

Check out any of the following tags to build the corresponding version. You'll need a POSIX-type system with the usual POSIX-type stuff installed, along with 64tass on the path. (Building these on Windows is an exercise for the reader. Sorry!)

The resulting ROM in each case is .build/exmon2.rom.

These ROMs are not Electron-compatible, though some stuff will work to an extent.

v2.02

Looks to be the newest version I've found so far. Probably recommended.

v2.02-alt

Doesn't properly support BBC B/B+ with a 65c02. It will assume your BBC has an ordinary non-CMOS 6502.

v2.01

All the problems of v2.02, and it doesn't support BASIC 4r32 either.

(Also a few code differences that I haven't looked at very closely - looks like there may be some issues with running code in other ROMs.)