[Coco] Read Coco floppies in my PC

[Chad H]

Hmm I also have a couple Teac 55's I think....but no 'sector not found' errors while working with true 360k disks formatted as 360k ...  it would be interesting to devise some sort of 'test procedure' one could perform to check %100 for cross compatibility reading/writing one drive's disks in the other...what I did to test them gave me reasonable asurance, but I have yet to see errors.

Here's how I'm setup for my CoCo disk 'swapping' ....
CoCo: FD-502 with 2 x PC 360k drives. (Teac/Panasonic)  ROM & OS-9 modified for 6ms stepping and double sided
PC: Win'98 with 1.2mb Chinon drive

How I test the drives...
1. Format a disk (A) 360k PC format
2.  PC DSKINI the disk with. DSK image
3. Use CoCo to BACKUP disk A to disk B
4. CoCo DSKINI disk A
5. CoCo backup Disk B to A
6. PC RETRIEVE disk A to test. DSK
7. PC 'FC' compare final test image with original

Michael Graham <mkgraham at gmx.com> wrote:

>Whoops, accidental send.
>
>My 1.2mb drive is a Teac FD-55GFR.  I was using IBM DOS 5.0.
>
>On 3/30/2012 11:15 PM, Michael Graham wrote:
>> On 3/30/2012 10:14 PM, Chad H wrote:
>>> What OS are you using?  What 1.b drive model?   Only time I get 
>>> errors on good media in my 98 box is when I mess upand try to format 
>>> a 360k disk as 1.2mb
>>>
>>> Michael Graham<mkgraham at gmx.com>  wrote:
>>>
>>>> I'm not sure how you pulled that off.  When I write with my 1.2mb drive
>>>> (with format /f:360), I always get 'Sector not found' errors reading
>>>> them with a 360k drive.  The other way around works, though, at least
>>>> until I write to the disk with the 1.2mb drive, then the disk becomes
>>>> unreadable.  I'm pretty sure it has to do with the fact that a 1.2mb
>>>> drive head writes narrower tracks than a 360k drive.  I originally 
>>>> would
>>>> have thought it was just something wrong with my drive, but I did a web
>>>> search after noticing this and found other accounts and an explanation
>>>> on a couple of websites.
>>>>
>>>> The same thing happens when I format a 720k floppy in a 1.44mb drive.
>>>> The 1.44mb drive can read it, but a true 720k drive cannot.  That's why
>>>> I have a 1.44mb drive hooked up to my PCjr as a second drive, even
>>>> though I can only use it in 720k mode;  It makes file transfer much
>>>> easier if I don't have to also write with a 720k drive.
>>>>
>>>> On 3/30/2012 9:53 PM, Chad H wrote:
>>>>> I have 9 360k pc-xt drives, all fully tested to read/write disks 
>>>>> formatted by 1.2 mb drives without problems....?????
>>>>>
>>>>> Michael Graham<mkgraham at gmx.com>   wrote:
>>>>>
>>>>>> Just FYI, most double-density (360k) drives won't read double-density
>>>>>> disks written on high-density (1.2M) drives.  I tried this when I 
>>>>>> first
>>>>>> got my PCjr, and it didn't work, so I had to swap the 360k drive back
>>>>>> and forth between my PCjr and my old desktop machine until I could
>>>>>> source another 360k drive.  I couldn't get disks written in a 1.2M 
>>>>>> drive
>>>>>> to read on my CoCo, either.  However, disks written with a 360k drive
>>>>>> will read back just fine on a 1.2M drive, as long as you don't try to
>>>>>> write to them.
>>>>>>
>>>>>> On 3/30/2012 8:20 PM, Bill wrote:
>>>>>>> The drives I just got are 1.2Mb, and I have tried several times 
>>>>>>> to format a
>>>>>>> 360K disk, but for some reason it won't let me. I type in the 
>>>>>>> command format
>>>>>>> b: /f:360 (which SHOULD work), but it gives me an error message.
>>>>>>>
>>>>>>> Has ANYONE been successful formatting a 360K disk in XP with a  
>>>>>>> 1.2Mb drive?
>>>>>>>
>>>>>>> Thanks
>>>>>>>
>>>>>>>
>>>>>>> -- 
>>>>>>> Coco mailing list
>>>>>>> Coco at maltedmedia.com
>>>>>>> http://five.pairlist.net/mailman/listinfo/coco
>>>>>> -- 
>>>>>> Coco mailing list
>>>>>> Coco at maltedmedia.com
>>>>>> http://five.pairlist.net/mailman/listinfo/coco
>>>>>>
>>>>> -- 
>>>>> Coco mailing list
>>>>> Coco at maltedmedia.com
>>>>> http://five.pairlist.net/mailman/listinfo/coco
>>>>
>>>> -- 
>>>> Coco mailing list
>>>> Coco at maltedmedia.com
>>>> http://five.pairlist.net/mailman/listinfo/coco
>>>>
>>> -- 
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> http://five.pairlist.net/mailman/listinfo/coco
>>
>>
>> -- 
>> Coco mailing list
>> Coco at maltedmedia.com
>> http://five.pairlist.net/mailman/listinfo/coco
>
>
>--
>Coco mailing list
>Coco at maltedmedia.com
>http://five.pairlist.net/mailman/listinfo/coco
>