15 Jun
2020
15 Jun
'20
8:41 a.m.
My fear is that one of the PALs has altered itself
from tin-whisker
migration (fuse regrowth) :(
I've finally looked at the printset for the VT240 and I must be
missing something....
The only PALs I can find are the 'logic units' in the video memory
updating circuitry. That circuitry is pretty much the same as .... the
Rainbow colour graphics board and I suspect the PAL logic is much the
same too. I have the Rainbow's PAL equations if you need them but I
doubt that's the problem.
-tony