[Coco] Need new disk drive...

[Joel Ewy]

Chuck Youse wrote:
> On Thu, 2008-09-18 at 08:04 +0100, Phill Harvey-Smith wrote:
>   
>> Gene Heskett wrote:
>>     
>>> On Wednesday 17 September 2008, Chuck Youse wrote:
>>>       
>>>> On Wed, 2008-09-17 at 21:25 -0400, Gene Heskett wrote:
>>>>         
>>>>> That controller MAY have a Fujitsu 8877 FDC chip in it.  This chip is one
>>>>> of the few that can be used at 500 kilobaud data rates, allowing DSDD
>>>>> floppy drives to be used at 1440 kilobyte size.
>>>>>           
>>>> Am I missing something?  Double-sided double-density 5.25" drives are
>>>> 360K, no?
>>>>
>>>>         
>>> If set for 40 tracks, double sided in the os9 descriptor then yes. 
>>>       
>> <pedantic mode>
>> Or 80 track single sided.....as IIRC some early Atari ST machines used, 
>> at least here in the UK.
>> </pedantic>
>>
>>     
>>>                                                                But I 
>>> believe that chip can have the high speed data rate hack applied, which means 
>>> the nearest $25 3.5" 1.44 meg drive with HD diskettes can be used in it.
>>>       
>> But then wouldn't that be DSHD ? Double sided, High density ? Was this 
>> what was sometimes refered to as Quad density, or was that 80 tracks as 
>> opposed to 40 ?
>>     
>
> "Quad density" (a misnomer, of course) 5.25" drives were 80 tracks,
> double-density.  720K per diskette.. not too common, but I remember the
> Tandy 2000 had 'em.
>
> C.
>
>   
I think you're right, Chuck.  I remember using a Sage in college that
used those "Quad Density" drives.  They weren't the same as the "High
Density" 1.2M.  Double Density was 48tpi, Quad Density was 96tpi.  I
guess by that measure, the 1.2M would be "Octuple Density," which is
undoubtedly why they just got called "High Density."

The Sage was an interesting bird.  68000, USCD P-system.  I remember it
had one castle/kingdom simulation type game on it that seemed pretty fun
at the time, though I can't remember the exact name.  All I can think of
is Kings & Castles, but that was a CoCo game. 
http://en.wikipedia.org/wiki/SAGE_Computer_Technology  Interesting as it
was, the CoCo was more fun.

JCE
>
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