5 Jun
2010
5 Jun
'10
7:03 p.m.
Gene Buckle wrote:
On Sun, 30 May 2010, Tony Duell wrote:
Gene,
Please let us know how you made out with this. There might be some
common failure pattern that would be nice to know if mine ever gives up
the ghost. :)
There's a ROM on there(DF autoboot ver 2.1 chip), and at least one PAL
chip (DFS PAL), and maybe another one DTACK?
Is it worth trying to read the ROM?
Is it possible to reverse engineer the PALs by hooking up a logic
analyzer? Are PALs normally just combinational logic? No timers,
counters, storage, and so on? Just formulas for combining inputs and
producing outputs?
Thanks
Keith
Can you explain the set-up, please. What is
connected to what, and where
the PSU is connected to (the A500 mainboard, right)?
Here's a picture of the board (well *A* board):
http://amiga.resource.cx/photos/dataflyer2000plus,5
Mine has the memory expansion conector installed.
The A500 works fine with this card installed. I did more checking and
it appears that there's a short between +5 and ground. I removed all
the chips to eliminate them as a potential cause and it's still reading
as shorted. The only components left on the board at this point are the
resistors, a pair of electrolytic caps and a pair of what I think are
tantalum caps.
Thanks for the suggestions Tony.
g.