Acorn ADFS
ADFS (Advanced Disc Filing System) is a floppy disc and SCSI hard disc filing system for the BBC Micro. It supports hierarchical directories, random access files, and the Acorn free space map format. ADFS plugs into the MOS filing system framework, providing implementations of OSFILE, OSFIND, OSGBPB, OSBGET, OSBPUT, and OSARGS. It also handles disc formatting, defect mapping, and file compaction. The ROM contains both the floppy disc driver (using the WD1770 controller) and the SCSI hard disc driver.
Annotated Disassemblies
| Version | Memory Map | Changes |
|---|---|---|
| Acorn ADFS 1.30 | Memory map |
References
Sources consulted
- tobylobster's BBC Micro MOS disassemblytobylobster's fully annotated disassembly of the BBC Micro MOS — a reference for the OSBYTE / OSWORD / OSFILE vector semantics and zero-page / workspace names ADFS relies on.
- Acorn ADFS User Guide (PDF)Official Acorn user guide covering ADFS commands, disc formatting, and file operations.
- Adaptec ACB-4000 OEM Manual (PDF)OEM technical manual for the ACB-4000 with SCSI command details and LUN-to-drive-select mapping.
- Hoglet's ADFS 1.30 disassemblyA BeebAsm-syntax disassembly that reassembles to byte-identical ROMs for multiple ADFS variants. Provided important structural guidance.
- Dominic Beesley's ADFS multi-target reassemblyA ca65-based multi-target reassembly covering many ADFS versions with well-named labels and modular driver separation.
- J.G. Harston's ADFS 1.30 disassemblyA BBC BASIC-embedded disassembly with informative block comments and entry/exit documentation for key routines.
Further reading
- Acorn Winchester Disc 110/130 Service Manual (PDF)Service manual for the Acorn Winchester drive enclosure, covering the Host Adapter PCB, SCSI interface, and 1 MHz bus connection.
- Adaptec ACB-4000 Series User's Manual (PDF)User manual for the Adaptec ACB-4000 SCSI-to-ST-412 disc controller used in Acorn Winchester drives.
- Acorn SCSI Host Adapter SchematicCircuit diagram of the Host Adapter PCB that bridges the 1 MHz bus to the SCSI interface at &FC40-&FC43.
