cliff_poole
Active member
I have a Strider B and C board which has two broken SIL devices marked CR084. They don't seem to be straight resistor networks from what I can tell. Does anyone know what they are ?. Does CR stand for Capacitor Resistor ?.
CPS SIL devices.
- Thread starter cliff_poole
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What have you found so far that suggest they're not resistor packs? It might be worth Stanley knifing off the compound given that this one looks permanently dead to see if there are any clues under the coating.
Any idea what function they perform in the circuit or what they are wired to? I can't really see a reason for having a bunch of RC delays in a circuit, but there again I don't design these things
Do they look like they're used as a pull-up/down function?
Any idea what function they perform in the circuit or what they are wired to? I can't really see a reason for having a bunch of RC delays in a circuit, but there again I don't design these things
Do they look like they're used as a pull-up/down function?
cliff_poole
Active member
By the look of things, they are connected between the connector CN10, then to a 74LS245, and from there I can't really tell.
The game doesn't run and I am unable to read three of the big mask ROMs. I'm just trying to decide whether to go on or to shelve it at the moment.
The game doesn't run and I am unable to read three of the big mask ROMs. I'm just trying to decide whether to go on or to shelve it at the moment.
From the circuit position I'd guess they are pull-ups. Do you get anything when you meter between pin1 and the others and what's the largest resistance range setting you've tried? Might be worth seeing if one pin of the holes is wired to 5V as that would support the "input pull-ups" idea enough to let you sub some normal resistors.
cliff_poole
Active member
Thanks for the ideas, I think I'd have given up if I hadn't posted
.
I'm pretty sure I have got it now. There were two of these on the board and both were broken, the picture above is both sides of the least broken one.
On the PCB, pin 1 goes to +5V and pin 10 (the last pin), goes to ground. I managed to chip off a bit of the black coating and found that the blobs on the back are 10nf capacitors. Pin 1 to pin 2 reads 1K; readings between any other two adjacent pins (except 10), are about 2K, so that looks like 8*1K pull up resistors. I am guessing then that the caps go between the inputs and ground, all commoned together at pin 10 although I am puzzled why there only appear to be four caps looking at the blobs ?.
Anyway, I am satisfied that this is nothing to do with why the game won't run. It is going back on the shelf now as I don't have any 40 pin EPROMS or a spare A board.
I'm pretty sure I have got it now. There were two of these on the board and both were broken, the picture above is both sides of the least broken one.
On the PCB, pin 1 goes to +5V and pin 10 (the last pin), goes to ground. I managed to chip off a bit of the black coating and found that the blobs on the back are 10nf capacitors. Pin 1 to pin 2 reads 1K; readings between any other two adjacent pins (except 10), are about 2K, so that looks like 8*1K pull up resistors. I am guessing then that the caps go between the inputs and ground, all commoned together at pin 10 although I am puzzled why there only appear to be four caps looking at the blobs ?.
Anyway, I am satisfied that this is nothing to do with why the game won't run. It is going back on the shelf now as I don't have any 40 pin EPROMS or a spare A board.
cliff_poole
Active member
Oh thats an excellent find, thanks !.
OK, I have checked with the meter again and here is my final rekoning.
OK, I have checked with the meter again and here is my final rekoning.
