[Coco] Re: Oddball disk format question

[Torsten Dittel]

> I was intrigued by Torsten's "physical" copy station using a 68HC11 and two
> drives.

"Physical" means I try to to do a 1:1 reproduction of the MFM signal the
source drive's head reads (which means: it's reading the phase changes
of magnetic flow). The problem is that the WD controller chip is
interpreting the data it reads. And it has some bugs with that (on
purpose if you ask me). It can write some irregular stuff which is
difficult to reproduce, because it's read as something which is
impossible to write.

> So I guess that would be single board computer for the explicit purpose of
> copying disks?

Actually it's a single chip computer, a so called Micro Controller. The
version I'm using has 2KB of EEPROM which can be programmed by its
serial port. It has various inputs and outputs, even an 8-channel ADC
and programmable digital inputs/outputs for various purposes like
counting, etc. The Assembler is quite similar to the 6809.

Torsten