sverre@lars.Seri.GOV (Sverre Froyen) (05/09/91)
Good news: My TEAC SCSI floppy is now performing to my satisfaction. I have set up the initialization so that it works with IBM PC formatted diskettes (1.44MB and 720kB). For now you have to format (low level) the diskette using another computer (easiest) or the rom monitor (moderately easy for 1.44 MB diskettes, horrible for 720 kB diskettes). So far I have only tested the drive with Minix file systems since I have (as yet) no working tools for reading and writing MSDOS files (anyone else looked at this already, e.g., commands/ibm/dosread.c). I have also made (and tested) a boot floppy with a copy of the Minix image and a root file system (for my own peace of mind and as insurance against future mistakes). Software changes: I created two new devices, fd0 and fd1, for low and high density, respectively. Accessing either of these devices will generate a mode select command (if necessary) and then issue the read or write command. Fortunately, this could be accomplished by changes to scsi_hi.c only. Observations: This drive does not recognize the DS/DD and HD diskettes on its own. It is your (my) responsibility to used the appropriate device (fd0 or fd1) when you access a diskette. The 4MB version of this drive will (if you get the right version) recognize the various diskette types and can be queried (using a mode sense) about the type, so you may want to consider this drive instead (it is only slightly more expensive but may be harder to find). Finally, the drive is unable to read/write Macintosh formatted diskettes (these use a different GRZ? encoding). This should not be a problem since the Macintosh can also read/write/format MSDOS diskettes (with MFM encoding). Finally-finally, you should be able to get 1.6MB out of the drive by using 1kB sectors. I have not tested this. I was going to post the diffs to scsi_hi.c but my modem port on the 532 appears to be hung. It will have to wait until tomorrow. Sverre -- Sverre Froyen sverre@seri.gov, sunpeaks!seri!sverre