[Coco] Re: [Color Computer] 1.44 disk
dsbrain at sbcglobal.net
Wed Aug 3 07:40:12 EDT 2005
Gene Heskett wrote:
> On Tuesday 02 August 2005 15:38, stacey wrote:
>>can u use 1.44 diskettes in a 720k drive will they work ok
> Generally speaking, no. The media for the HD disks has a magnetic
> coating thats harder magneticly, and requires more drive to make an
> adequate recording. It might work 5 minutes after you do it, but 2
> weeks later all bets are off.
> I've noticed that todays crop of aftermarket 3.5" floppies also seem
> to have another problem. Insert an HD diskette, and they demand a
> 500 kilobaud data rate and will not function at all at the 250
> kilobaud rate the coco controllers can muster. Same drive with a DD
> diskette in it works flawlessly at the coco's 250 kilobaud data rate.
I held off on this discussion but now I must jump in as we have been
round & round this topic in the TI-99 groups and I can state with 100%
confidence that there is absolutely no (zero, nada, zip) difference in
the magnetic coercivity between 720k and 1.44m brand-name floppies; the
only major difference is the number of holes in the plastic. On the
TI-99 they can be used interchangably with 100% confidence &
reliability. It is only the 5.25" disks where it makes a difference; the
magnetic coercivity is different between DD (hub ring) & HD (no hub
ring). Also, all 3.5" drives spin at the same speed whereas 5.25" DD
drives spin at 300 rpm and HD drives spin at 360 rpm. In another (older)
life I was an electronics technician with a repair shop and still have
much info on electronic and computer hardware. So if you desire I can
try to find my huge hardware/upgrade guides and quote the exact passages
from those book as I have on the other groups.
If I understand you there are problems between the 720/1.44 drives/disks
on the CoCo. This is most likely from some other cause (such as the
difference in Kbaud rate as you suggested). On my TI-99/4a system (1.44m
drive reading/writing 360k) and my Atari MegaST2 system (720k drive) I
commonly have used both types of disks to carry files between it and my
main PC with no problems, even 2 years later. But I MUST use 360k 5.25"
drives/floppies on my TI-99 system as 1.2M simply don't work (side note:
the uncommon QD 720k 5.25" drives DO work at 360k but only with DD/QD
floppy disks just as on the 360k drives).
As usual YMMV and always back-up important files in more than one place.
Due to political oppression I'm seeking a Canadian or European
"It is dangerous to be right when the established authorities are wrong"
This OS/2 uptime is 7 d 11 h 37 m 27 seconds
------------------------ Yahoo! Groups Sponsor --------------------~-->
<font face=arial size=-1><a href="http://us.ard.yahoo.com/SIG=12hogsgp1/M=362329.6886308.7839368.1510227/D=groups/S=1705005378:TM/Y=YAHOO/EXP=1123076472/A=2894321/R=0/SIG=11dvsfulr/*http://youthnoise.com/page.php?page_id=1992
">Fair play? Video games influencing politics. Click and talk back!</a>.</font>
Brought to you by the 6809, the 6803 and their cousins!
Yahoo! Groups Links
<*> To visit your group on the web, go to:
<*> To unsubscribe from this group, send an email to:
ColorComputer-unsubscribe at yahoogroups.com
<*> Your use of Yahoo! Groups is subject to:
More information about the Coco