Level42
New member
OK, so I've got the machine running, and of course the old battery has been removed, but I want to keep my "high" scores !
I've seen the solution from Tranquility Base with a loose phone battery and some rather long wires, but I'd prefer to install a lithium cell on the board instead.
The Lithiums will last at least 10 years and this mod has been done often on Williams boards.
However, Williams boards don't charge the batteries. Berzerk does.
In theory, I should be able to "block" the charging supply with a simple diode. Once the machine is off, the battery will supply it's voltage through the diode.
Not sure if that will work OK on a ZPU board.
The other alternative is using a Ni-MH battery like this:
This _can_ be charged and provides the right kind of voltage. However, I was wondering if the IC to store the hi-score data on might be drowning out this one too quickly ?
I suggest these because we use them on fire alarms main PCB's. These keep the programmed data save whenever the mains AND the back-up battery pack are disconnected. So....they're well....uhm....sort of "available" for me
I've seen the solution from Tranquility Base with a loose phone battery and some rather long wires, but I'd prefer to install a lithium cell on the board instead.
The Lithiums will last at least 10 years and this mod has been done often on Williams boards.
However, Williams boards don't charge the batteries. Berzerk does.
In theory, I should be able to "block" the charging supply with a simple diode. Once the machine is off, the battery will supply it's voltage through the diode.
Not sure if that will work OK on a ZPU board.
The other alternative is using a Ni-MH battery like this:
This _can_ be charged and provides the right kind of voltage. However, I was wondering if the IC to store the hi-score data on might be drowning out this one too quickly ?
I suggest these because we use them on fire alarms main PCB's. These keep the programmed data save whenever the mains AND the back-up battery pack are disconnected. So....they're well....uhm....sort of "available" for me