[Coco] 8inch floppy on a coco

[Bruce W. Calkins]

Well, as someone else mentioned: 8" drives share the data transfer speed 
of the 5.25" 1.2 and 3.5" 1.44 Meg drives.  The adaptation for that data 
transfer rate was done on the early 26-3022 12 volt disk controller and 
to the best of knowledge no one has figured out any alternative method. 
That said, please do keep us informed as to progress and methodology.
Bruce W.

On 05/17/2018 12:12 PM, rietveld rietveld wrote:
 > I managed to get it to spin up but i cant get the disk to format    I 
was hoping to just format it as a 35 track disk just as a proof of concept
 >
 > ________________________________
 > From: Coco <coco-bounces at maltedmedia.com> on behalf of Salvador 
Garcia via Coco <coco at maltedmedia.com>
 > Sent: May 17, 2018 10:41:02 AM
 > To: CoCoList for Color Computer Enthusiasts
 > Cc: Salvador Garcia
 > Subject: Re: [Coco] 8inch floppy on a coco
 >
 > Actually, hardwarewise, the two floppies are not all that different. 
I recall back in the early 90s we got hired by bank to come up with an 
interface so that they could stop using 8" drives with their Phillips 
PTS system. Instead, they wanted to use a high density 1.2M floppy 
drive. My colleague, who was responsible for the hardware, found that 
most of the signals were compatible, expect a for a few (maybe even just 
one). The incompatible signal(s) just needed to be inverted. 
Softwarewise, it was not straightforward at all. The floppy's format 
used a standard IBM format which was different than anything used by 
MS-DOS PCs. I had to bypass the ROM BIOS (venerable INT 13h) and write 
my own drive access routines (using ROM BIOS code as a template).
 >
 > Salvador
 >
 >
 >      On Wednesday, May 16, 2018, 9:26:17 PM CDT, Sean 
<badfrog at gmail.com> wrote:
 >
 >   I didn't think an 8 inch drive would work with a CoCo?  Isn't it a
 > completely different data rate and size than what a disk controller
 > supports?
 >
 > On Wed, May 16, 2018 at 7:28 PM, rietveld rietveld 
<rietveldh at hotmail.com>
 > wrote:
 >
 >>   I apologize for how badly my phones 'auto correct ' Un corrected 
my post
 >>
 >> I am just really excited to finally be able to use these drives
 >>
 >> Sent from my BlackBerry Passport Red Edition.
 >>   Original Message
 >> From: rietveld rietveld
 >> Sent: Wednesday, May 16, 2018 8:26 PM
 >> To: Coco mailing list
 >> Reply To: CoCoList for Color Computer Enthusiasts
 >> Subject: [Coco] 8inch floppy on a coco
 >>
 >>
 >> I finally scores some new old stock 8 inch disk. I am hooking an eight
 >> months inch drive to my coco as we speak.
 >>
 >> I am going to post a video showing how ridiculously cool this looks.