as@aipna.ed.ac.uk (01/09/91)
> I guess this can't be avoided without changing the hardware setup. But > I hope Acorn is aware this 'flashing' *really* looks quite silly, ...j I wonder ... One obvious hack around this is: ask the controller for the previous sector on the same track. Once it starts arriving (too fast), ask the controller for the one you really want, and wait: either set a hardware timer to interupt you just before it comes round or sit in a software loop. When sector arrives, transfer data using programmed i/o. The catch: you have to have interrupts disabled, for at least one floppy sector (around 1centi-sec). I.e. instead of losing your display you have to halt traffic on the serial port, etc. You could of course use the wait for the proper sector to come round to try and make this as painless as possible. I.e. if sensible, send XOFF on the serial port, etc. An OSBYTE to allow people the choice - no display and fast floppy, OR real slow floppy and repeated disabling of interrupts, events, etc might also be helpful. This could be a dumb idea ... but that ZX-80 style flashing sure as hell doesn't fit with the ``personal workstation'' story. Andrew -- Andrew Stevens, JANET: as@uk.ac.ed.aipna Dept. of Artificial Intelligence, ARPA: as@aipna.ed.ac.uk 80 South Bridge, UUCP: ...!mcvax!ukc!aipna!as Edinburgh University, EDINBURGH