Tim's own version of the Catweasel/Compaticard/whatever

No, I'm not even suggesting that the CatWeasel is ver close to what was called for in the earlier discussion regarding an archival format for data normally distributed or contained on FD's. What I was getting at was that, while the CatWeasel seems to work OK for some things, and, in fact, quite a few, it probably doesn't read/write hard sectored disks and it probably doesn't allow minute adjustment sector-by-sector of the data on the diskette in order to make the format and the data fields within it all clock-coherent. It was my suggestion that the device be supported with software to allow not only that data be extracted from the bitwise oversampled data recorded as in Tim's buffer, but also that software be generated to permit the data to be reduced, essentially, to just the data in the data fields with some set of information (which was TBD when I last looked) implying the nature of the format in which it was recorded. Further, it was to be able to write the data into any known format, including known formats not supported by the controller available to the user. My suggestion was that a good test would be to write an Apple][ diskette using a PDP-8. I've also suggested that a "perhaps even better" approach might be to generate FDC code for the Scenix SX to do the job of several different and increasingly scarce FDC chips. This would easily support the function I was going on about earlier. It's easy, of course, to wachs poetic about what things could or should be. I've got a first-attempt at an EPP interfaced board down on the shelf in the basement. It may, someday, have the abilities I've suggested, but I'm not interested in making a large investment in time until I have convinced myself that when the hardware's done, there will be a point in having built it. Without adequate support software to interpret and regenerate the bitstream recorded from a floppy drive, I'm not sure the hardware's worth building. I did want to demonstrate interchangeability between 5-1;4" diskettes written on my Apple-][ and my Ampro, for which I have the needed hardware (if I can find my Apple . . .). I'm quite certain that will work, though I don't know it's needed. OTOH, there are diskettes which are no longer available or for which drives are such a maintenance headache it would be easier to handle them with a different drive type, except the system doesn't support them. That's where I was headed. The Catweasel may be a good model to keep in mind, but the comment about bits moving around over time does give me pause. Have a look at my embedded remarks below, plz. Dick ----- Original Message ----- From: Tim Mann <mann(a)pa.dec.com> To: <classiccmp(a)classiccmp.org> Cc: Richard Erlacher <richard(a)idcomm.com> Sent: Tuesday, July 04, 2000 8:45 PM Subject: Re: Tim's own version of the Catweasel/Compaticard/whatever I'm inherently version of I simply mean that the Catweasel and Tim's buffer/sampler board are two shots at two different targets. There's little point in comparing them unless the overlap more than they appear to do in the writing I've seen up to now. unfortunately, Perhaps it has the capability, but as I said, it's after a different end. We're not trying to replace FDC's here, but rather simply want to read, save, and rewrite formats foreign to our systems with as little pain as possible. see I guess that's as good a reason as any. 48 MHz oscillators are cheap and available almost everywhere. Maybe those would serve in a similar device.