bobmon@iuvax.UUCP (Robert Montante) (10/03/86)
In article <208@csustan.UUCP> guest@csustan.UUCP (Chris Rhodes) writes: >In article <1091@kontron.UUCP> cramer@kontron.UUCP (Clayton Cramer) writes: >> >>DISKCOPY and FORMAT both require that the processor run at 4.77 MHz. >>(Timing dependencies involving the disk controller.) The FAST88 kit >>I have gives you a switch to go back to 4.77 MHz for this exact reason. >> >>Clayton E. Cramer > >Gee, my pclone, which supposedly runs at 8mhz (norton says 1.6 relative >speed, haven't done the math yet) runs diskcopy and format perfectly >fine....in fact, all my utilities (and all my software for that matter) >[...] A likely reason for one FORMAT to fail is that it was written too specifically for a 4.77MHz machine. Programs such as FORMAT are customized somewhat for different machines that get MS-DOS. My MS-DOS, for example, is for an 8MHz Zenith; and FORMAT among others displays a version banner that specifies it is by and for Zenith machines.
rde@ukc.ac.uk (R.D.Eager) (10/22/86)
I have been reading the stories/theories/ideas about using an 8Mhz
machine with interest. I suspect (as noted) that the V20 has nothing to
do with the problems; I ran a V30 for months in an 8086 machine with no
problems at all (and that with a FORMAT from a manufacturer who would
have been unlikely to do anything clever).
I suspect that those machines that DO work either have different timing
loops in the BIOS, or they turn the speed down (on software switchable
machines) while accessing the floppy disks. Of course, there are also
the hardware problems like DMA overrun....
Incidentally, I have a so-called 'turbo' (software switchable) 4.77/8Mhz
machine. Last night I fitted an LED to show if it was in 'fast' or
`slow' mode (I had been having trouble with ill-behaved programs that
turned the speed down without my immediately noticing). Today I see that
whenever I access the floppies (yesterday I only used the hard disk) the
speed light flickers, and goes out if there is heavy floppy activity.
Thought some of you might be interested in this drivel. You could type
'n' if not, but it's a bit late now....
--
Bob Eager
rde@ukc.UUCP
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