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marty
04-21-2008, 02:51 PM
Hi all;
After working on my altair 8800 about a week ago, I suddenly don't have a working out (323) instruction... :confused: :confused: I have not checked the clock and their phases, but what else should I check ???? Front Panel, CPU board, upper address 8t97's, etc... I have loaded other programs in by the front panel switches, to test if other instructions are working, which they seem to be working ok....
THANK YOU Marty

Grant Stockly
04-21-2008, 10:36 PM
How have you determined that the out instruction is not working properly?

SOUT is generated by the 8212 and is buffered through IC H. Is it possible one of those is bad?

marty
04-24-2008, 03:05 PM
Hi Grant;
I have both tried to do an in with the front panel switches and set the Accumulator to a value and tried to out it to the front panel.... and also it won't out to the 2-sio board , that was my first clue, that I was having trouble...
I checked the timing with the clock's and got them to work even better than before... I used variable resistors to get what I wanted on the scope.... so that is not the problem...
So next is to check if Sout is getting out, since my high address seem to work, even though I haven't extensively checked them.... Sout is showing up on the front panel light, so I assumed it was working, maybe not ...
AS Always THANK YOU Grant !!!!! Keep up the good work !!!!!
THANK YOU Marty

marty
04-26-2008, 08:40 PM
Hi all;
I checked the clocks and they are alright!!!!
The Sout is working also !!!!!!!!!!!!!! out to the mother board,,, still have to check the 2-sio board and see why it won't work.... that may give me a clue why nothing else is working also !!!!!!!!!!!!!
THANK YOU Marty