Would a CR2032 battery be enough to save scores in Punch-Out?

MaximRecoil

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Would a CR2032 battery be enough to save scores in Punch-Out?

The original battery holder has 3 AA batteries in series for 4.5v. A CR2032 is 3v. Obviously the 3 AA batteries don't stop saving scores the instant they drop a hair below 4.5v, so there must be a range of voltage that will work; but is 3v too low?
 
I tried it with a CR2032-with-solder-tabs that is probably 15 years old (because it came out of an SNES cartridge ... measured 2.9v), and I soldered to the holes that the battery terminal wires go to (this board was already missing its battery holder due to battery leak damage).

I played a quick game of PO, long enough to get the top score, and then shut the game off. Without batteries, when you start the game again the scores will all be back to defaults of course. Well it saved my high score, so I can confirm that it works. With a brand new CR2032 battery, it should work for at least 15 or 20 years I'd guess.
 
I don't think 3v would be enough. You can get 4.5v coin cells, they aren't common but they do exist.

Yeah, I didn't think it would be enough either. I forgot that I kept that battery that I replaced in the SNES cartridge, or I would have just tried it in the first place.

By the way, these batteries would be perfect:

batteryns.jpg


They are what I use to replace SNES batteries. Since they are soldered in place (the same as original NES/SNES cartridge batteries are), there is no chance of a momentary interruption of power like can happen with battery holders. That happened to me with my SPO boardset with the 3 AA batteries in the holder. One day all my scores were just gone, even though the batteries were less than a year old, tested fine, and continued saving scores afterwards fine.

Edit: As far as I know, all 4.5v coin cell batteries are alkaline. I specifically wanted the benefits of lithium.

Edit 2: Here's a picture:

pobattery.jpg


All of that bare copper showing is where I scraped off solder mask that had been damaged by the battery leakage (which happed before I ever got the board). The battery acid was soaked into it, and it was all discolored and bubbling up; and in one spot it had eaten completely through the solder mask and was attacking the copper trace with a large spot of brownish corrosion. I was able to remove all of that, and all of the traces are intact. I want to coat the bare sections of copper with something now; I've heard nail polish works pretty good.
 
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Succesfully installed holders plus 2032's on Berzerk pcb sets ( requires a diode to stop the charging !!!!) and Joust 2 boardset. I wouldn't go soldered because it will run out in one point of time and then you will have to get the PCB out and resolder again....Good quality holders are really tight and can't loose contact unless you totally ruin it...
 
For charging circuits (Berzerk and others) you can look at the schematic and remove the resistor that sits around the blocking diode. The resistor is to allow for charging and the diode is to block the full power supply current from reaching the battery when the game is powerd up. On a Neo Geo it's a 470 ohm resistor next to the battery. Of course, leave the diode in place or your battery will explode. ;)

RJ
 
Succesfully installed holders plus 2032's on Berzerk pcb sets ( requires a diode to stop the charging !!!!) and Joust 2 boardset. I wouldn't go soldered because it will run out in one point of time and then you will have to get the PCB out and resolder again....Good quality holders are really tight and can't loose contact unless you totally ruin it...

Yeah I was thinking about that, but that would be like 20 years down the road. Also, the legs on the solder-tab batteries are long enough to be bent to match up with the PCB holes as well as sit up off the board by about a quarter inch. It needs that height clearance because the D4 and D5 components are in the way:

clearancek.jpg


I pulled a CR2032 battery holder out of an old dead PC motherboard to try first, but its legs were too short to even bend to match the holes in the PCB, much less have the height clearance over D4 and D5. I'd consider a good quality battery holder if I could find one with long enough legs. The battery I put into this board isn't permanent; it was just a test. When I do it for real I'll be using a new battery, rather than one from the mid '90s.
 
For charging circuits (Berzerk and others) you can look at the schematic and remove the resistor that sits around the blocking diode. The resistor is to allow for charging and the diode is to block the full power supply current from reaching the battery when the game is powerd up. On a Neo Geo it's a 470 ohm resistor next to the battery. Of course, leave the diode in place or your battery will explode. ;)

RJ

Tip I learned from Mark Spaeth is to use a shottky diode because they have a very low voltage drop.
 
I'd recommend getting some PCB lacquer and spraying that exposed area as soon as possible. A schottky diode has a drop of about 0.3-0.4v compared to 0.6-0.7v of a standard diode.
 
I wouldn't go soldered because it will run out in one point of time and then you will have to get the PCB out and resolder again....Good quality holders are really tight and can't loose contact unless you totally ruin it...

So I've been thinking some more about this, and a simple circuit boad that would screw down in place of where the original battery holder is screwed down, would make a nice, neat solution. Something like this:

punchoutbatteryreplacem.png


example2leih.jpg


It would mount to the existing holes in the PO PCB, using short standoffs of course.

I need to learn how to make prototype PCBs.
 
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So I've been thinking some more about this, and a simple circuit boad that would screw down in place of where the original battery holder is screwed down, would make a nice, neat solution. Something like this:

punchoutbatteryreplacem.png


example2leih.jpg


It would mount to the existing holes in the PO PCB, using short standoffs of course.

I need to learn how to make prototype PCBs.

Go get the free download of EAGLE and play with it. BatchPCB.com has a plug-in for EAGLE and some tutorials you can use to start learning it. The output from EAGLE can be uploaded straight to BatchPCB for validation and building your prototype board.
 
Go get the free download of EAGLE and play with it. BatchPCB.com has a plug-in for EAGLE and some tutorials you can use to start learning it. The output from EAGLE can be uploaded straight to BatchPCB for validation and building your prototype board.

Awesome idea. It looks like it is quite inexpensive too (this PCB is only 1.5" x 1.5" [2.25 square inches]). I wonder if they can print white text, lines, etc. on the boards as well. It isn't necessary, but it would make it look more professional.
 
Awesome idea. It looks like it is quite inexpensive too (this PCB is only 1.5" x 1.5" [2.25 square inches]). I wonder if they can print white text, lines, etc. on the boards as well. It isn't necessary, but it would make it look more professional.

They can. You just put what you want on the appropriate layer.
 
Never had the need for this. On both the Berzerk and Joust2 boards I could find a ground area on the solder side so that I could drill a hole and solder the minus of the holder to that GND area....looks like you can do that on this board too.
 
Never had the need for this. On both the Berzerk and Joust2 boards I could find a ground area on the solder side so that I could drill a hole and solder the minus of the holder to that GND area....looks like you can do that on this board too.

Yes I could, but I don't want to drill into my PO/SPO boardsets, nor do I want it to look "hacked". If I make this PCB, it will be a drop-in replacement for the original 3 AA batteries holder, it will look professional, and it will be 100% reversible.
 
Here's how my Berzerk PCB looks:

web.jpg


web.jpg


Underside:
web.jpg


Looks better than the original bulky battery and I wouldn't want any extra PCB to be hanging around...Sorry but I just think those PCB's would be total overkill.......just MHO, to each his own of course.....
 
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Etching a PCB to do this would be a waste of time and money... You could make exactly the same thing with a little piece of perf board in two minutes.

-Ian
 
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