5 Jun
2005
5 Jun
'05
6:15 p.m.
You have to remember that the PC group didn't *want* to do some of
the things that were done to the PC. It was specifically lobotomized so
as not to compete with the Display Writer. According to a friend of
mine who worked there (and was the lead developer on the PC Jr (another
political victim)), one of the reasons for the 8088 was because they had
Intel blue box development systems around. There was a strong internal
camp that wanted a 6809 in the PC.
--jc
Eric Smith wrote:
Patrick wrote:
Err, I think you have the memory limit wrong
(I'm assuming you meant
448kB), 640kB (or 64kB on the original motherboard if you don't use a
memory expansion card) is more accurate.
On the original PC, the limit was less than 640K. It was determined
by the DIP switch settings, and there weren't settings that went as
high as 640K. To convince the BIOS and DOS to use more memory, you
had to run a program that fiddled with the pointers in low memory.
Ok, I don't understand that... Colorburst is
(on NTSC), about 3.58 MHz,
which isn't easy to derive from 4.77MHz. I highly doubt IBM's reason
for using that speed had anything to do with (at least NTSC) video.
Yes, that was the reason. They had a 4x colorburst crystal (14.31818 MHz).
They divided by three for the CPU clock, and by four for the colorburst.
Eric