Richard let me know that the FB+ is using a CR1225 battery. I picked one up today but I don’t have the tools to open a VB cart. I purchased some precision mini pliers but they are to thick to fit. Tried some other stuff as well but I seem to be just causing damage to the screw.

I want to buy a gamebit off eBay but I am unsure what size the VB screws are. Are they 3.8mm?

I was thinking about modding a screw driver but I think it would be about the same price as a gamebit (under $4).

Anyways, I’m curious about what size the screw is and if anyone has any ideas on how to open it?

Thanks!

As I said on IRC, it is indeed 3.8mm. I’ve found that the cutting type of pliers can usually get the screws out. The pointy ends of the jaws fit in the little notches, and you can turn the screw if you’re careful.

However, you might have further difficulties once you get it open. I don’t know for sure, but I’m assuming the FB+ uses a button cell with solder tabs welded on, just like the official carts. If this is the case, your “off-the-shelf” cell can’t be used directly, without some kind of mounting that can be soldered to the board. There might be a tutorial online about attaching standard batteries to a game cartridge. I would do a search on “Game Boy battery replacement” and the like. Of course, if yours is the kind with solder tabs, just ignore me 😛

some good news for FB+ users. below is a response from richard.

BTW it does not require any soldering to replace the battery, it fits in a holder on the PCB. All you need is the screwdriver for the 2 screws that hold the cart together.

i’m looking at buying one of these: 3.8mm gamebit

i did buy that bit and a screwdriver for it. it cost me about $16 with shipping. i got it in less than a week. the bit is made of a cheaper metal, its not a sears craftsman quality but it does the job. i recommend the screwdriver as it took some minor torque to get the screw off.

replacing the battery was really simple, i just popped out the old one with a mini flat head screwdriver and then slide in the new one.

at first the rom flashed to the cart was still not saving. i reseated the battery and flashed a new rom, that one has been fine so far. i’m not yet 100% sure the problem was the original battery. the battery cage seems really tight so i don’t think it was the seating of the original battery. only time will tell if it is something else, like a bad connection. the old battery was about two weeks old by the time i received the FB+, but it could have been sitting around. if the new one is holding a save 2 months from now i’ll assume it was battery related.

anways, just wanted to post an update =).

Lester Knight wrote:
some good news for FB+ users. below is a response from richard.

BTW it does not require any soldering to replace the battery, it fits in a holder on the PCB. All you need is the screwdriver for the 2 screws that hold the cart together.

I missed this when you posted it, so… Really?! I didn’t know they made holders that small. I might have to ask Richard where he bought them and see if I can get mine hands on some for all my Gameboy save batteries that have died…

I assume it’s this style holder: http://www.sparkfun.com/products/7948 ? If so, you should make sure the copper pad underneath is clean… sometimes the copper oxidizes, causing bad contact. With those holders, the PCB itself is the bottom contact, rather than typical battery holders, which have metal contacts for + and -, which get soldered to the board.

DogP

I’m pretty sure I’ve discovered the problem. I recently bought some CR1225’s in bulk and they were held down to the tray with clear tape.

This left a residue on the top (+) side of the battery, which seems to be enough to intermittently disconnect the power from the SRAM (and hence erase the game-save). I now clean them with acetone.

The battery holder from sparkfun is very similar. Only I use the surface mount version.

DogP wrote:
I assume it’s this style holder: http://www.sparkfun.com/products/7948 ? If so, you should make sure the copper pad underneath is clean… sometimes the copper oxidizes, causing bad contact. With those holders, the PCB itself is the bottom contact, rather than typical battery holders, which have metal contacts for + and -, which get soldered to the board.

DogP

Right, I thought of this a few minutes after I posted. I remember when I was looking for a battery holder to replace a battery in one of my Genesis games, I came up with those mostly. I seem to recall that someone who did those kind of replacements said that they had never found a plastic battery holder that was small enough to fit in a Gameboy cartridge.

That’s good news for Flashboy+ owners about the batteries just being dirty. I wish cartridge manufactures had just used battery holders instead of soldering the battery on. I can’t imagine it would have been that much more expensive.

I think they probably didn’t want to use battery holders because then you could just replace the battery easily, meaning… you’d most likely spend time on the game you’ve already bought rather than buying whichever newer game(s) the same people who made that game made 😉

a “I’m afraid of soldering so I guess I’ll have to buy the re-make (if there is one)” situation

(also, if your battery was defective around the time they were still selling said game (but after the 30 day warranty) they would probably use the excuse of “we might mess up the soldering (and it takes time/effort) so just buy a new cartridge”)

but thats just a theory, really

MineStorm wrote:
I’m pretty sure I’ve discovered the problem. …a residue on the top (+) side of the battery, which seems to be enough to intermittently disconnect the power…

the battery i took out has no residue on it at all, its clean as a whistle. the replacement was from radioshack in a 1 battery per pack display. it was stored in plastic, the outside of the plastic was glued to the cardboard display pack, and also does not have any residue on it at all.

in my case, this is not the explanation as to why the first battery stopped holding the save. i noticed with the first battery that the save was gone after different lengths of time. when i got the FB+ Richard had flashed a game and left a save on there. i tested but the save was not there, so that was a little more than a week of storage time. i flashed some stuff to it, had a save, and that save was there for at least a day. the next time i made a save it was gone in hours. the next time it didn’t store the save. it looks like it was the battery, but i’m not 100% sure. i do not own a meter to test the battery but what i did do was connect a 3volt LED to the battery and it lights up bright as day. i’m pretty sure the LED could be pulling off the last of the charge, so that test really isn’t conclusive.

when i first replaced the battery i had mario crash flashed there. after playing the save was still not saving. i then reseated the battery and flashed a new rom, that rom has had its save stored. so this problem could be a seating issue or the copper pad as dogp suggested.

the last game i flashed was wario on 4/3/11 and is still holding the save. i am not playing that much but i am checking every couple of days to see if it is still there.

Lester, if you are willing to spend $14 on a gamebit, why not spend $10 on a multimeter? It’s always good to at least be able to measure battery voltage.

Fwirt and GYF, I assure you cost is always the driving force. By using the battery with tabs, they also reduce their BOM from 2 parts to just 1, and they no longer need someone to install batteries in every cartridge which is a huge savings in itself. Plus, the way they did it is a better electrical connection and has no worries of having the battery somehow pop out accidentally. And with a clip, the solder joint is always under tension, so dropping the cartridge could break the connector (I had a key fob with a similar connector that would break after being dropped a few times, I had to fix it at least 3 times). And really, the battery provides 10+ years with no service, so who cares? It is only now that we are running into this problem.

But bottom line is always cost. Sad reality is that accountants run the world. Doesn’t matter if you are selling something for $1 or $10,000, saving money, no matter how small, adds up.

Yeah, you’re right about having to pay someone to insert the battery, I hadn’t thought about that. I also didn’t think the mechanical stress of being dropped would be an issue. The engineers know what they’re doing, and I know the savings add up, ($0.01 over 1 million cartridges is $10,000 after all!) but I still wish it was possible to make things easier on people who want to use the product later… Things just aren’t built to last anymore. 🙁

It is a little less then a year since I replaced my battery. I haven’t used my VB at all over the past 8 months. I set it up tonight and found that my battery is once again not saving. I should have access to a meter tomorrow, and I’ll test to see what the voltage is. I can’t believe that the battery would be dead from being stored for the past 8 months, but then again, we do have extreme temperatures here. It was over 90 F most of the summer and now its around 40. I do not have central heart or air so everything here feels the environmental changes. Perhaps that has something to do with it?

I think there is definitely the possibility that the problem does not lie with the battery. My FlashBoy Plus has never been able to save games since I first got it, so I’ve wondered if there could be some other issue causing it rather than a dead battery. I don’t usually care to save games on my FlashBoy Plus anyway, so I’ve never tried to pursue getting the problem of the lack of save function resolved.

i flashed over fishbone about 12 hours ago and that high score is still there. it seems that when i flash a new rom that the save works, but if i leave that rom on there for an extended period of time that i eventually lose the save.

i really need to do a lot more debugging before i can actually say that my last statement is true. i’ll keep checking the cart of the next few days and see if it keeps the save.

a bit late for this reply…

with a new battery (my 3rd) the cart seems to be saving fine. i had wario land on there months ago, enjoyed it, then flashed a different game. lastnight i flashed wario back and my old save is still there. right now i’m blaming the battery and extreme heat combination for my issues. i’ll continue to test with this battery throughout the year and see what happens.