[Coco] [OT] Commodore 64 slow floppy

[Johann Klasek]

On Wed, Jan 22, 2014 at 01:20:53PM -0500, Al Hartman wrote:
> My understanding of why the Commodore Disk Drive was so slow is that there 
> was a bug in one of the chips used in the drive, and instead of correcting 
> the chip, they just slowed down the drive so as not to encounter the bug.

Right.
Here you got the read. 
http://jderogee.tripod.com/projects/1541-III/files/IEC_disected-IEC_1541_info.pdf
The PDF contains the "A brief history of the
IEC-bus" by Jim Butterfield on page 18, which explains the background very well.
Not to say, a "sad history of" ...

> It was possible to work around the bug with software and get faster speeds 
> which is why we have all the turbo loaders and things like JiffyDOS on the 
> C64/C128.

Usually not by means of hardware shifting, but using parallelism
(mutliple data lines) with very lean handshake.

[..]