25 Apr
2009
25 Apr
'09
12:10 p.m.
This is why I try to make backups of programmed parts
while the device is
still working. Of course some manufactures plow the protection fuse, so
you can't easily read the device out (although for PALs, I believe it's
always possible to deduce the logic equations with a bit of work without
having to dump out the fuse map, there is no hidden internal state). A
suprising number of classic computers, though, have unprotected PALs, etc.
A pal-cracker would be very useful here...I do pal reverse engineering
by analysing the inputs and outputs of the device, and trying to devise a
similar circuit (did it in many MSX "lost" products, for example the 2.0/2+
transformation kits from DDX, and now I'm trying to crack the GALs in the
Sunrise IDE). Funny work, for an unemployed guy like me