O.T. c64 slow drives. was

[Lance F. Squire]

Lennart Sorensen wrote:
> On Wed, Jul 12, 2006 at 04:13:46PM -0400, phiscock-g851W1bGYuGnS0EtXVNi6w at public.gmane.org wrote:
> 
>>This puts me in mind of the Commodore 64 floppy disk drive. To save money,
>>Commodore had the same processor reading the drive mech as talking to the
>>IEEE bus. As someone said:
>>
>>'Loads programs faster than you can type them in!!! (But only just..)'
> 

The 'inside' story to this slowness is quite interesting.

First, the 1541 started as a Vic 20 drive, and was acceptably fast.

Apparently, a timing error in the 64 roms caused the reads to miss the 
next sector. This caused the system to have to wait for the sector to 
come around again.

As this was slower than running the drives in 'slow' mode. They just 
shipped the 64 coloured drives with 'slow' mode set as default, rather 
than tossing the burnt roms and fixing.

That and the 'bash the head against the stop' till you were sure it was 
homed, were 'Brilliant'...

Most drives used a micro switch or other device to know when the head 
reached 'home' position.

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