🚀 go-pugleaf

In article <1293@hoptoad.uucp> farren@hoptoad.UUCP (Mike Farren) writes:
>In article <437@moncol.UUCP> john@moncol.UUCP (John Ruschmeyer) writes:
>>Recently I've been looking at ads for programs to read/write alien disks on
>>an IBM compatable. One thing I've noticed, though, is that none of them
>>support the formatting of single density disks (old Osborne I, TRS-80 Model
I, etc.).

>>Is there some imitation of the disk controller in an IBM-PC which
>>prevents single ensity operation or is it some limitation of the BIOS?

>Single density disk controllers write the data to the diskette at 250K bit/
>sec.  Double density controllers do so at 500K.  The IBM controller has only
>the 500K clock on board - it would take a hardware change to allow it to
>do 250K. Not impossible, just impossible with the standard controller.

The olivetti M24 (ATT 6300) has a single- double density switchs-
circuit on the motherbord floppy controller. A bit in a floppy contol
register does the switch. I don't have documentation with me.
I think that this machine wil boot from single density floppys.
At boot the bios switch between both modes when it can not read your
boot floppy.

henk peek  henkp@nikhefk.uucp   seismo!mcvax!nikhefk!henkp.uucp