Around 1991, Arxe Systems Limited released a high density floppy disc interface for the Acorn Archimedes range, to allow the use of HD discs from the then new A5000 on earlier models. This interface was either sold on its own or with an integral SCSI controller. Hugo Fiennes wrote the code for the SCSI controller, while Dave Acton wrote the floppy support (I don't know who did the hardware). Hugo has a support page for the SCSI side, while this page attempts to give details of the floppy side.
Dave kindly allowed me to use the floppy code from the now defunct Arxe card on my SuperIO project. He therefore sent me the source of his latest version of the code (circa 1993), and I ported it to my hardware and fixed a few bugs. Available here are the original source that Dave sent me, and my ported version.
Original Arxe source
These are the original archives that Dave sent me, containing v0.89 of QuadFS and v0.54 of QuadFSFiler. They're essentially Dave's working directory with various bits of test code and notes to people.
My ported version
To port the code to my hardware, I had to make a number of changes. In particular, at that point I didn't have a copy of AAsm, so had to convert both modules to build under the Basic assembler. I also had to interface the code to my podule's APIs (rather than just assuming things about the podule's memory map, and to support more than one podule in the machine), and in the process deduce a fair number of vital details of the Arxe card (since I've never seen one). My cryptic development notes are available if anyone can make use of them, as are basic notes on what's in the archive (it includes both of these).
The main archive of sources is here. This includes code to make QuadFS pretend to be ADFS, which appears to be better than KillFS, although needs support in the QuadFS module and requires you not to have an ADFS hard drive. The module should be portable with a little effort to any FDC in an Acorn machine, which satisfies the basic conditions that it is '765 compatible, and has its interrupt line connected to FIQ. If you would like to port this code to other hardware or have any other queries, mail me (theo [at@] markettos.org.uk), and I should be able to help. It's been a while since I worked on it, but I'll try to remember things, although I can't promise anything...
Page by Theo Markettos (email at theo [at@] markettos.org.uk), last modified 2001-01-09
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