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simonden

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I am using a B board that has been suicided for a long time and was using de-suicide ROMs (Team Avalaunch).

It never had a problem with EXC5 with de-suicided ROMs until installing the CPS2 Multi, however now it seems to have a problem (blank screen) every time I turn it off and back on again. Shorting EXC5 resolves the problem (measure 0V) until next time I turn it on. As I don't want to open up the B Board every time I want to turn on the multi I am looking at a solution.

My question is will removing the capacitor at EXC5 resolve the problem? Or not? Or will it cause other problems?

I suppose that i could just run 2 wires from EXC5 to an external button so I can short it outside the case however I would prefer a permanent solution if possible.
 
hey just curious. Rather than shorting exc5 each time your problem occurs, what if you simply reprogram a game with the lcd instead?

Occasionally I have a problem where I power on my multi cart and it goes to a solid red screen, like a suicided board. I simply just choose a game again (even if it was the last one I had working prior to re-suicide), program it on the lcd, and it loads up the game fine again. Sometimes my problem happens after one day, sometimes an entire week.

Let us know
 
Sadly it doesn't work for me, just stays solid (usually Black or Green) screen until I power off and short EXC5.
 
That's very weird, but I guess yes. Remove only one leg of the capacitor and see if that solves the problem.
 
It's possible that your board has the pullups at the security writer inputs broken. That cause the pins to be left floating, which could cause spurious inputs which in turn could cause "random" garbage to be programmed on the security chip.

Because the Darksoft multigame pulls the 68k reset low while flashing and pulling reset low is what enables the security writer inputs you might have it receiving some "random" programming during the while the board is flashing.

Resistors R13, R6 and R14 near CN9 do that function.

Older boards (boards without CN9) don't seem to have R13 and R16 but they have R6.
 
I'm looking at this thread, and had tried to short exc5. Does it need to be on or off when shorting? With such a small cap I would think that it would short out in less than a second.
 
EXC5 is a filter capacitor for the security battery +3v line. Only short it with the system off.
 
l_oliveira said:
EXC5 is a filter capacitor for the security battery +3v line. Only short it with the system off.
Click to expand...
Do you happen to know what EXC1-5 are for and which ones (if any) can be removed?

Edit -- I went ahead and did some tests for SCIENCE! My preliminary findings:
EXC1 and EXC5 -- Seem to be okay to remove
EXC2 (particularly this one), EXC3, and EXC4 -- Cause crashes if removed

I don't recommend anyone else remove these caps. You might break your board. Only time will tell if this one re-suicides again with EXC1/EXC5 removed.
 
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