18 Mar
2000
18 Mar
'00
8:49 p.m.
Tony Duell wrote:
From what I remember, this machine is painful to take apart, with
dozens of screws. Unlike the 380Z which involves taking out 2 screws
and pulling the top of the case.
Six on the bottom, four for the keyboard and another four for the Mini
Station Options board, which is largely unpopulated. I can see from the
mismatched screws on the bottom that it has been taken apart many times
before!
The video RAM, at least the text mode RAM, seems to be
mapped into
the I/O space, but I've not really looked at that.
Poking all the RAM locations from Front Panel gave me that impression,
along with a few crashes, but hey, Reset and straight back into Front
Panel! I think that the high res graphics are also I/O mapped, which is
why they are so slow.
I wrote a sprite routine for the 480Z, but it was only flicker-free for
sprites with a width of 20 pixels or fewer, because I had to output to
one port to give me a time window to the RAM, and then pump bytes
containing four pixels through another port. I wish I'd kept all those
listings now.