https://github.com/ivanizag/bbz
Run 6502 programs using the Acorn MOS on a modern operating system as a console application
https://github.com/ivanizag/bbz
6502 acorn bbc-micro emulator
Last synced: 5 months ago
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Run 6502 programs using the Acorn MOS on a modern operating system as a console application
- Host: GitHub
- URL: https://github.com/ivanizag/bbz
- Owner: ivanizag
- License: mit
- Created: 2021-07-25T14:57:08.000Z (almost 5 years ago)
- Default Branch: main
- Last Pushed: 2025-12-24T15:16:38.000Z (6 months ago)
- Last Synced: 2025-12-26T06:14:18.864Z (6 months ago)
- Topics: 6502, acorn, bbc-micro, emulator
- Language: Go
- Homepage:
- Size: 1010 KB
- Stars: 7
- Watchers: 1
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# bbz - Acorn MOS for 6502 adaptation layer
Used to run 6502 programs using the Acorn MOS on a modern operating system
as a console application. It runs BBC Micro language ROMs.
## What is this
This is a MOS for 6502 execution environment. It's a 6502 emulator that
intercepts the calls to the Acorm Machine Operating System (MOS) and
services them as a native console application on the host.
This is not a BBC Micro emulator. It does not emulate the BBC Micro
hardware, just the 6502 processor.
BBZ is a console program, it tries to look and feel as a modern console
application not as a BBC Micro. There is command history accesible with
the up arrow and control-R. Control-C behaves as the BBC Micro Escape key
to interrupt long running programs. Control-C twice will exic BBZ back to
the host.
This program is heavily inspired on [Applecorn](https://github.com/bobbimanners/Applecorn),
"a ProDOS application for the Apple //e Enhanced which provides an environment
for Acorn BBC Microcomputer language ROMs to run."
References:
- [BBC Microcomputer System User Guide](https://archive.org/details/BBCUG)
- The Advanced User Guide for the BBC Microcomputer
- [BeebWiki - 8-bit Acorn Computer Wiki](http://beebwiki.mdfs.net)
- [Applecorn source code](https://github.com/bobbimanners/Applecorn)
- [The MOS Reassembly for the BBC Micro](https://tobylobster.github.io/mos/mos/index.html) and [raybellis's mos120](https://github.com/raybellis/mos120)
- [beeb-fstest test suite](https://github.com/tom-seddon/beeb-fstest)
## Features
- Can run BBC BASIC and most of the language ROMs.
- Saves and loads files from the host filesystem.
- Readline like input with persistent history.
- Can load up to 16 sideways ROMs, the unused slots are filled with sideways RAM 16K expansions.
- Most of the MOS entrypoints and VDU control codes are defined.
- Does some of the mode 7 text coloring using ANSI escape codes on the terminal. Try `VDU 65,129,66,130,67,132,68,135,69,13,10` on BBC BASIC.
- OSCLI comands suported:
- *| */ *FX *BASIC *DELETE *DIR *EX *EXIT *HELP *INFO *LOAD *RUN *SAVE *SPOOL *TYPE
- *CAT filename: dumps the file contents using the BBC Micro character set and VDU conversions
- *HOST cmd: execute a command on the host OS. Example: `*HOST ls -la`
- *BYE or *QUIT: exit to host
- *ROMS: List the loaded ROMs
- 6502 emulation provided by [iz6502](https://github.com/ivanizag/iz6502)
## Usage
```
bbz [flags] [filename]
```
`filename` is the filename of the ROM to run (the same as `-rom0`). By default, it
uses the BBC Basic ROM in `BASIC.ROM`.
AvaIlable flags (to put before the ROM filename if present):
```
-M dump to the console the MOS calls including console I/O calls
-c dump to the console the CPU execution operations
-m dump to the console the MOS calls excluding console I/O calls
-p panic on not implemented MOS calls
-r disable readline like input with history
-s dump to the console the accesses to Fred, Jim or Sheila
-rom0 string
filename for rom 0 (slot 0xf)
-rom1 string
filename for rom 1 (slot 0xe)
-rom2 string
filename for rom 2 (slot 0xd)
-rom3 string
filename for rom 3 (slot 0xc)
-rom4 string
filename for rom 4 (slot 0xb)
-rom5 string
filename for rom 5 (slot 0xa)
-rom6 string
filename for rom 6 (slot 0x9)
-rom7 string
filename for rom 7 (slot 0x8)
-rom8 string
filename for rom 8 (slot 0x7)
-rom9 string
filename for rom 9 (slot 0x6)
-rom10 string
filename for rom 10 (slot 0x5)
-rom11 string
filename for rom 11 (slot 0x4)
-rom12 string
filename for rom 12 (slot 0x3)
-rom13 string
filename for rom 13 (slot 0x2)
-rom14 string
filename for rom 14 (slot 0x1)
-rom15 string
filename for rom 15 (slot 0x0)
```
## Install
### From binary
Get the latest version from the [releases](https://github.com/ivanizag/bbz/releases) page in Github
### From source
bbz is a standard go project, build with `go build .`
### From the Snap store
bbz is named [mosbbz](https://snapcraft.io/mosbbz) in the Snap store:
```
$ sudo snap install mosbbz
```
You will need to download a ROM, for exmaple [BASIC.ROM](https://github.com/ivanizag/bbz/raw/main/BASIC.ROM), and invoke as `mosbbz`':
```
$ mosbbz BASIC.ROM
```
## Usage examples
Running BBC Basic:
```
$ ./bbz
bbz - Acorn MOS for 6502 adaptation layer, https://github.com/ivanizag/bbz
BASIC
>PRINT "HELLO"
HELLO
>10 PRINT "HEY"
>RUN
HEY
>SAVE "TEST"
>NEW
>LOAD "TEST"
>LIST
10 PRINT "HEY"
>X
Mistake
>*HOST ls -l TEST
-rw-r--r-- 1 casa casa 14 jul 30 20:04 TEST
>^Csignal: interrupt
```
Log of the MOS calls (excluding the most verbose output API calls):
```
$ ./bbz -m ROMs/Forth_103.rom
bbz - Acorn MOS for 6502 adaptation layer, https://github.com/ivanizag/bbz
FORTH
COLD or WARM start (C/W)? C
[[[OSRDCH()=0x43]]]
[[[OSARGS('Get filing system',A=00,Y=00) => 105]]]
[[[OSBYTE82('Read machine high order address',X=0x58,Y=0x00) => (X=0xff,Y=0xff)]]]
[[[OSBYTE84('Read top of user mem',X=0x58,Y=0x00) => (X=0x00,Y=0x80)]]]
[[[OSBYTE83('Read bottom of user mem',X=0x58,Y=0x00) => (X=0x00,Y=0x0e)]]]
FORTH
OK
2 1 + .
[[[OSWORD00('read line',BUF=0x0542,range=20-ff, maxlen=80)='2 1 + .']]]
3 OK
```
Using mode 7 colors:
Using several ROMs at once:
```
$ ./bbz -rom0 BASIC.ROM -rom1 ROMs/Forth_103.rom -rom2 ROMs/LISP501.ROM -rom3 ROMs/COMAL.rom -rom4 ROMs/MPROLOG310.rom -rom5 ROMs/Pascal-1.10-Compiler.rom -rom6 ROMs/Pascal-1.10-Interpreter.rom
bbz - Acorn MOS for 6502 adaptation layer, https://github.com/ivanizag/bbz
(tip: uppercase is usually needed)
BASIC
>*ROMS
ROM F BASIC 01 (L)
ROM E FORTH 01 (SL)
ROM D LISP 05 (SL)
ROM C COMAL 16 (SL)
ROM B micro PROLOG 80 (SL)
ROM A Pascal 10 (SL)
ROM 9 Pascal 10 (SL)
RAM 8 16K
RAM 7 16K
RAM 6 16K
RAM 5 16K
RAM 4 16K
RAM 3 16K
RAM 2 16K
RAM 1 16K
RAM 0 16K
>*HELP
BBZ 0.0
FORTH 1.03
LISP 5.01
COMAL
micro PROLOG 3.1
PASCAL 1.10
>*LISP
LISP
Evaluate : (* '*FORTH)
FORTH
COLD or WARM start (C/W)? C
FORTH
OK
OS' *COMAL'
COMAL
→*PASCAL
Pascal
%*PROLOGUE
micro PROLOG
29184 bytes free
&.
```