[Coco] Connect CoCo Floppy drive to Windows PC

Gene Heskett gene.heskett at verizon.net
Mon Jan 19 00:30:08 EST 2009


On Sunday 18 January 2009, Torsten Dittel wrote:
>Gene Heskett schrieb:
>> [...] this is the first time I've read a cogent explanation of it.
>
>I once found that explanation here:
>
>http://www.moria.de/~michael/floppy/floppy.pdf
>
>On page 10 it reads:
>
>"[...] The NEC 765 controller goes to sleep for about 1.8ms after the
>index hole is sensed and expects still to read gap 1 when it wakes up.
>It works fine for floppies formatted using the 765, because it will
>always generate the format as specified above. The WD 1797 controller,
>though, does not have a command to format a track, but writes a given
>pattern to the track when formatting it. If the pattern has a too short
>post index gap, for example because it is a format which tries to
>maximise the usable disk space, the 765 controller will fail to read the
>first sector. To make things yet more complicated, the 765A controller
>only sleeps for 0.6ms, which means it is less sensitive to shorter post
>index gaps. [...]"
>
>Regards,
>Torsten
>
Neat, thanks.

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
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