...and back on this! After several *untested* boards bought here & there ($$$
£££) ... I still didn't see anything on this XY monitor!
Ok, no more complain! Let's what I can do to fix this!
I'll use the cleanest Battlezone board I own, the one who -at least- does the self test procedure!
So this one gives me 8 long tones and 1 long high tone, which is indicates a problem at RAM D2
RAM at D2 :
Got this stuff since several years now! It's time to use it...
RAM D2 replaced, but now the self test procedure indicates me a problem at RAM C1
OK, let's put a new ram @ C1 location, it cannot be a bad thing after all!
Power on ... and ... no boot at all! I mean even no self test procedure.
maybe something goes wrong during the un/soldering procedure?
Bingo, I cut by mistake a track. Let's quickly fix this
But still no boot!
Here's the test I've done to figure out what could be wrong now :
If I remove RAM at D2, the game goes again into the self test procedure, and of course indicate me a problem at RAM D2!
OK, so maybe the new RAM I've used for D2 is also bad? I trying with an other one -> no boot!
So let's use the ram I've replaced at C1 and use it at D2 -> no boot!
In conclusion, whatever the RAM I place at D2 location, this prevents the board to boot and go to the self test procedure!
Damw, I double / triple checked all the tracks linked to the D2 ram, and see no mistake! What else could be wrong ?