Re: Sig. analysis on Atari 6502 boards

all you have to do is wire the data lines to the binary equivalent of NOP... So
if the NOP is 0x86 (which seems to pop into my head but I can't remember for
sure...

  D7(msb)- +5V
  D6 - GND
  D5 - GND
  D4 - GND
  D3 - GND
  D2 - +5V
  D1 - +5V
  D0 - GND

If 0x86 isn't the opcode for NOP then this is wrong of course. But you get the
idea.

Matt Rossiter - Verio Southern California wrote:
>
> I have some Kurz Kasch instructions for doing signature analysis on Atari
> 6502 boards.
>
> Step #2 says "Plug in 6502-A (Atari) NOP into socket with the textool
> locking handle at the pin 1 location".
>
> - you then put the cpu into the socket and close the locking handle.
>
> - the signature analyser is connected by hooking clock to pin 37, start
> and stop to pin 25 and ground to pin 21.
>
> My question is - how would you go about making a 6502-A NOP? Can you do
> this by just grounding certain pins on the cpu socket or is it more
> involved? Would this set up work for comparing signatures in most of the
> Atari manuals or do you actually need to use the CAT box?
>
> Just wondering...
>
> Matt
Received on Mon Sep 20 00:17:06 1999