4mb STE White Screen

[Dan1975]

Hi.

When I turned on my STE earlier the screen flashed a few times then just went to a white screen and nothing else happened. The reset button did nothing and switching it off and on again made no difference. Where should I start as had been working perfectly before now

[exxos]

PSU recapped ?
Bad connection on simms ?

[thecaver99]

PSU recapped ?
Bad connection on simms ?

PSU is from one of my other STs and is working fine,
the caps were replaced before i got the board and extremally badly and half were missing but have now been replaced and all connections made to the correct traces.

ive just beeped out all the RNs and found broken connections from 4 of them and they have all now been fixed.
i now have the cpu out of HALT and when powered on i can see activity for a few seconds then it drops off, the cpu is still not halted, thats a real plus.
the diag cart powers on but doesn't kick off.

simm sockets are not broken and are clean, i have also tested connection from the chip to then pins on bottom of board, fairly sure they are making connection.

its getting better as small faults are found and fixed.

[rubber_jonnie]

PSU recapped ?
Bad connection on simms ?

PSU is from one of my other STs and is working fine,
the caps were replaced before i got the board and extremally badly and half were missing but have now been replaced and all connections made to the correct traces.

ive just beeped out all the RNs and found broken connections from 4 of them and they have all now been fixed.
i now have the cpu out of HALT and when powered on i can see activity for a few seconds then it drops off, the cpu is still not halted, thats a real plus.
the diag cart powers on but doesn't kick off.

simm sockets are not broken and are clean, i have also tested connection from the chip to then pins on bottom of board, fairly sure they are making connection.

its getting better as small faults are found and fixed.

You might want to consider a diag cart, can be very helpful.

[Dlfrsilver]

PSU recapped ?
Bad connection on simms ?

It's a case of what happens when the reset circuit driven by a capacitor is dead, making the STE stuck in the reset loop, and 68000 halted .

[exxos]

It's a case of what happens when the reset circuit driven by a capacitor is dead, making the STE stuck in the reset loop, and 68000 halted .

But he says pressing the reset switch does nothing. When the reset caps are bad, it tries to reset before the system has powered up and crashes. Pressing the reset switch solves that as the system has powered up at that point and the cap becomes irrelevant.unless the cap has shorted out internally which I've not seen or heard happening yet.

He also says the system runs a few cycles ... Sounds like it's trying to run ROM and crashes. Also sounds like the board has various track damage and likely has a lot more .

[Dlfrsilver]

It's a case of what happens when the reset circuit driven by a capacitor is dead, making the STE stuck in the reset loop, and 68000 halted .

But he says pressing the reset switch does nothing. When the reset caps are bad, it tries to reset before the system has powered up and crashes. Pressing the reset switch solves that as the system has powered up at that point and the cap becomes irrelevant.unless the cap has shorted out internally which I've not seen or heard happening yet.

He also says the system runs a few cycles ... Sounds like it's trying to run ROM and crashes. Also sounds like the board has various track damage and likely has a lot more .

oh! so sweet well he is out for some fun on it, ain't it ?