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davidgiven
IBM3740 type FM single density profiles
How do I create FM IBM3740 type single density format profiles?
Are the supported formats purely predefined profiles that can be overridden or are they hard coded?
Peter
You can specify a textproto file as a profile name and it'll load that at runtime, allowing customised profiles. The built-in ones are compiled into the binary for convenience. You can see the source for the built-in ones in src/formats.
Do you want to read or write IBM3740 disks? For reading, you could probably just use the generic ibm profile, which will attempt to autodetect the format. It sometimes gets confused and you might need to tell it what the base sector ID is (see the acorndfs format). Writing is harder. Do you have a reference for the disk format I could use?
David,
I would like to do both read and write.
RM 380Z supports both standard 8" IBM3740 single sided disks (26 spt, 128 byte sectors FM, 77 tracks) and 5.25" disks formatted in an IBM 3740 mode (16 spt, 128 byte sectors FM, 40 tracks).
380ZD & 480Z have intelligent controller that also support and IBM 34 disk format. 8" IBM 34 single sided [26 spt, 256 byte sectors MFM, 76 tracks + trk0 which is IBM 3740 FM]. 5.25" IBM 34 single sided based - [9 spt, 512 byte sectors MFM, 39 tracks + trk0 which is in IBM 3740 mode (16 spt, 128 byte sector FM)]
BTW How do I specify 'sequential' vs 'interleaved' file format ie disk side 0 followed by disk side 1 or purely in cylinder order (cyl0, cyl 1 .. cyl n - trk0h0,trk0h1,trk1h0,trk1h1 ...) for .img file format?
A slight further complication is that side 1 sectors are also identified as h0 rather than h1.
Peter
That sounds straightforward. I'll need more data on the format for writing --- in particular, I need to know the size of the gaps between records in the disk.
Regarding the image order: right now the format's hardcoded to CHS, but adding support for HCS ought to be easy. I'll get on to it soon.