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

From: allisonp <allisonp_at_world.std.com>
Date: Tue Jul 4 09:06:27 2000

> *I* buffer the pulses on the read data line by simply recording
>a "1" bit if there was a pulse in a window, and a "0" if there wasn't.
>I sample at 4MHz, meaning that a complete revolution of a floppy
>requires most a megabit of RAM. I also buffer information such as
>index pulse data (essential for decoding many hard-sectored floppy
formats.)


Sounds like a variation of the "Wells" controller ca. 1976, used 1x4k
memory to buffer up all the the disks bits. Lots of SSI ttl to
serialize/deserial
the bits in and out of the ram but otherwise simple and functional.

Check early BYTE or KB for the article on it. His design was limited to
mfm
(then the only thing used) but it would take little to deal with that.

>Would it be worth writing up my new floppy disk data buffer so that
>others could improve on it? Would anyone be interested in unstuffed
and/or
>stuffed PCB's? Should I give it a name? (The "Timweasel", anyone? I
>gotta think of a better name!)


If you would, please. I'd find it interesting.

Allison
Received on Tue Jul 04 2000 - 09:06:27 BST