5 May
2005
5 May
'05
4:13 p.m.
All the IBM 8088-based PCs had ROM BASIC. That was not
really useful for
The PC/AT does too...
very much, except that you had a functioning computer
even if you started
it without a boot diskette. When the XT came around, we also got COBOL
It's _very_ useful when you've got a malfunctioning disk controller and
want to send bytes to various registers on the card to figure out what
the problem is. (If that sounds like the voice of experience, you're
right. The 765 o nthe IBM disc controller can be reset in software IIRC,
and one of the chips -- either the output port latch or an inverter, I
forget -- failed on the card in my XT. Being able to toggle that port bit
by hand let me find the problem in a few seconds).
-tony