# Non volatil game boy saves (done on Pokemon Yellow, but problem on Pokemon Gold)



## yafeee (Apr 14, 2013)

Hi !

Recently I saw this post : http://forums.benheck.com/viewtopic.php?f=18&t=38664

To sum up, he replace the S-RAM chip of the original cartridge with a F-RAM chip (non volatil save). At the end a guy conclude that the FM18W08 chip is perfect to Pokemon Gold/Silver cartridge (he tried and it works).


I decided to apply this mod to my Pokemon Gold cartridge (I already lost my saves and replaced the battery 2/3 times). But a FM18W08 chip was not so easy to find, so I read some datasheets and found the FM1808 (old version of the FM18W08) as a solution. I ordered it from China, and tried to solder it on my Gold cartridge. Unfortunately, I didn't manage to have a working game (no save, and sprites in black and white). But I soldered the chip to my Yellow cartridge and it works.

Is it possible that I didn't solder the chip correctly on my Gold cartridge ? In fact, I had to insist, and solder/desolder to have a working Pokemon Yellow. If the chip is not adapted to Pokemon Gold/Silver, I will try to find a FM18W08, but I don't know where. I also have to buy a new Pokemon Gold, my cartridge is fucked up.

Edit: Thanks to Wolffangalchemist for giving us a working solution. Here is his solution for 2nd gen carts. Tested, it works great 



wolffangalchemist said:


> EDIT:
> figured it out, wired it up, fired it up, and was very pleased.
> i used aMB85R256 F-ram chip instead of a FM1808 either should work.
> images for those who need would like to give it a go and showing it working.
> ...


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## GBA rocks (Apr 20, 2013)

Cool project.

You may also be interested in the Drag'N'Derp card

http://derpcart.com/features.html

You would lose the Real Time Clock of the real Pokemon Gold cartridge though.


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## yafeee (Apr 26, 2013)

This card seems interesting, but very expensive, and I want to mod the real cartridge.

I tried again on a new Pokemon Silver cartridge. As a result : the save dosen't work and I have graphic glitches (photos below). These are the same issues as my first attempt.

I really don't know why. I tried with and without alimentation on the F-RAM chip.


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## raulpica (Apr 26, 2013)

Maybe the F-RAM chip is faulty? The soldering seems fine. Or maybe the "old" version has something that doesn't make it work with newer Pokémon games..

Anyway, sick project, I might do the same!


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## pyromaniac123 (Apr 26, 2013)

How much does the FM18W08 cost? Cheapest I've found is $5.93 for 1.


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## yafeee (Apr 26, 2013)

I tried with two different chip, on two different cartridge (Gold and Silver), and had the same issues. My Yellow moded cartridge is fully working, using one of the chip I used on Gold, so the chip is not faulty.

The original S-RAM chips are:

- lh52256cn-10ll on Blue, Red and Yellow

- bs62lv256sc-70 on Gold, Silver and Crystal



pyromaniac123 said:


> How much does the FM18W08 cost? Cheapest I've found is $5.93 for 1.


 
Oh ! Where did you found FM18W08 ? Actually, I buy FM1808 chips from ebay at 9.6 USD.


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## pyromaniac123 (Apr 26, 2013)

yafeee said:


> I tried with two different chip, on two different cartridge (Gold and Silver), and had the same issues. My Yellow moded cartridge is fully working, using one of the chip I used on Gold, so the chip is not faulty.
> 
> The original S-RAM chips are:
> 
> ...


 
http://www.aliexpress.com/item/FM18W08-FM18W08-SG-FM18W08-SGTR-RAMTRON-STOCK-IN-CHINA/667731292.html

If you are planning to do this to more than 1 cart.

http://www.aliexpress.com/item/FM18W08-SG-FM18W08-RAMTRON-SOP28-Free-shipping/751079156.html

More expensive but quicker than ordering 1 at a time.


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## yafeee (Apr 26, 2013)

pyromaniac123 said:


> http://www.aliexpress.com/item/FM18W08-FM18W08-SG-FM18W08-SGTR-RAMTRON-STOCK-IN-CHINA/667731292.html
> 
> If you are planning to do this to more than 1 cart.
> 
> ...


 
Thank you ! I think I will buy the second one (5pieces). But before, I will try to understand why the FM18W08 should work instead of the FM1808.

Edit: I just bought 5 FM18W08 from Aliexpress, I'll post the results when I'll receive my order.


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## Rabby250 (Jun 9, 2013)

Hello,

Sorry to bump this, but I had also run into exactly the same problem *with FM18W08*.

The detailed issues are:

After selecting "CONTINUE" from the menu after splash screen, the game will show that the save file you're going to load has "no player name (blank or null string), no badges and 0:00 play time". Pressing A afterwards will bring you to a blank screen where the game freezes (therefore the save file can never be loaded successfully). This is kinda strange, as in usual cases of corrupted saves the game will inform you when you select "CONTINUE", and force you back to the menu.
Almost all full-scale sprites (Trainers, Characters and Pokémons) and visual effects in battle (move appearances) will be displayed in black-and-white (not even gray-scale), but map sprites and palettes are normal. The main character sprite in the trainer info screen (where you check your badges) is the only known exception, which will be shown in color for unknown reasons.
The screen will show glitches during save overwrite confirmation dialog (the second yes/no option in a save), some other dialog (for example, when you're setting the day of week of your Pokéwatch) and between battle animations. In addition, the warning info - which should show up only if you are going to overwrite a previous save with a new game - will always show up, even when you are overwriting your current save.
The game will never ask you to reset your clock even if your battery was dead; instead, it automatically "sets" the time with a random (?) value dependent of the console you are using (for me, the time is always Thu. 10:15 for my GBA #1, Mon. 02:07 for my GBC, and Thu. 06:07 for my GBA #2 when testing with identical game cart and save file).
 
I believe this is not an issue related to the original SRAM, as the original SRAM on my testing cart (a Japanese Gold) was LH52256CN - the same one used in yafeee's RBY.
In fact, I've checked all my Gen I/II carts and found SRAM chips from 4 different manufacturers which share most of the specs, so the chip compatibility issues should be little to none.
(The only exception in all Gen I/II carts is *Japanese Crystal, which uses 1Mbit SRAM*. It's a pity that I couldn't find a matching FRAM to replace it.)

Guess we have to contact the guys who succeeded in the original thread to figure out what went wrong.

BTW yafeee, is the FRAM you're using a FM1808B? I'm considering one of those, but maybe I'll put it on hold if 1808B also fails. (Too bad I wasn't able to stop you from getting FM18W08.)


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## yafeee (Jun 21, 2013)

Hi Rabby !

I sent a message to the author of the original thread (on mod retro forum, I don't find how to register on benheck), but he didn't respond for the moment. I will post his answer here if I'll receive a response from him.

About the FM1808B, I didn't use that one. I have 1808 only !


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## qwertymodo (Jan 3, 2014)

I'm a member here as well, you could've PM'd me 

It's hard to say what the issue is... first of all, buying IC's from AliExpress is hit-or-miss. Especially when they're offering them at 50-75% off wholesale prices. I'd start by ordering from one of their official distributors to ensure that the product is legit. Also, as has been stated here, they used several different SRAM IC's at various points in their production, and they are interchangeable, but different games did sometimes use larger capacity chips. The FM18W08 is 256Kbit, so if a game uses 1Mbit, you're out of luck, since I don't know of anybody that manufactures 5V F-RAM in 1Mbit capacities, and certainly not in a SO-28 package. Check to make sure that the game you're transplanting is 256Kbit. If it's 64Kbit instead, the FM16W08 should work. The only other issue I know of has to do with the way the chip enable signals differ between asynchronous SRAM and F-RAM. I know that for the games I've tested, the MBC pulses the /CE signal for every R/W cycle, but if it holds the /CE signal low for multiple consecutive R/W cycles, it won't work, because although SRAM allows that, F-RAM requires a falling edge for each cycle. If that's the case, then you'll have to cut a trace and add some glue logic. Sorry, I don't really have time to test it out myself, but I'm happy to answer any questions for anybody who wants to try it for themselves.

Edit: Didn't realize how old this thread was... sorry :/ Any way, if anybody who has tried this can tell me where the earliest point where you experience glitches on a brand new game is, I may be able to do some testing, but I need to know where the glitches occur or I'll just be poking around in the dark...


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## Rabby250 (Feb 27, 2014)

Hello qwertymodo, thanks for the reply.



qwertymodo said:


> first of all, buying IC's from AliExpress is hit-or-miss. Especially when they're offering them at 50-75% off wholesale prices. I'd start by ordering from oneoftheirofficialdistributors to ensure that the product is legit.


For my attempts, I purchased 5 FM18W08 directly from Mouser and fully reproduced yafeee's issue with them, so I think it could hardly be an FRAM-side issue.



qwertymodo said:


> Also, as has been stated here, they used several different SRAM IC's at various points in their production, and they are interchangeable, but different games did sometimes use larger capacity chips. The FM18W08 is 256Kbit, so if a game uses 1Mbit, you're out of luck, since I don't know of anybody that manufactures 5V F-RAM in 1Mbit capacities, and certainly not in a SO-28 package. Check to make sure that the game you're transplanting is 256Kbit. If it's 64Kbit instead, the FM16W08 should work.


All Pokémon games except Japanese Crystal use 256Kb SRAMs, so the root cause wasn't related to this either.
(For 1Mb games, the most possible candidate I could find was Everspin's MRAM, although it only comes in 3.3V .)



qwertymodo said:


> The only other issue I know of has to do with the way the chip enable signals differ between asynchronous SRAM and F-RAM. I know that for the games I've tested, the MBC pulses the /CE signal for every R/W cycle, but if it holds the /CE signal low for multiple consecutive R/W cycles, it won't work, because although SRAM allows that, F-RAM requires a falling edge for each cycle. If that's the case, then you'll have to cut a trace and add some glue logic. Sorry, I don't really have time to test it out myself, but I'm happy to answer any questions for anybody who wants to try it for themselves.


Is it possible that different MBC chips of the same kind (for example, different MBC3 chips) could generate different pulse patterns?
I'm asking this because in my current attempts so far, all Pokémon games with MBC3 will (and will only) run into this issue,
and the only success case was Pokémon Yellow, which uses MBC5.
However you did succeed on Pokémon Red (U) (should be an MBC3), which made me very confused.

And BTW, after getting frustrated, I tried a bizarre combo of Pokémon Gold ROM + MBC5-based main board,
and it actually worked - until I found out that you could never use Box 7 (or 8) in Bill's PC.



qwertymodo said:


> Edit: Didn't realize how old this thread was... sorry :/ Any way, if anybody who has tried this can tell me where the earliest point where you experience glitches on a brand new game is, I may be able to do some testing, but I need to know where the glitches occur or I'll just be poking around in the dark...


You can reproduce this issue easily by following the steps below:
1. Find a Pokémon game with MBC3 and replace the RAM:

Yellow in Japanese region
Red/Blue in US region
Gold/Silver in any region
Crystal in any region except Japanese
2. Play the game until Professor Oak shows up for the first time;
you will know that you have ran into the issue if you see:

In RBY, nothing (the dialog was running, but no sprite)
In GSC, Oak's sprite in binary black and white (see yafeee's DSC01858.JPG)
3. Try to save once and restart to load your game:

In RBY, you can load your game (only the sprites are gone)
In GSC, you save will be corrupted
Thanks again for helping out!


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## qwertymodo (Mar 17, 2014)

Thanks for the details, I'll look into it when I get a chance, but it's finals week right now, and I have a ton of projects on my plate.  Also, I don't come around here very often, so chances are, I will forget about this thread.  If you want, feel free to hit me up by emailing to my username at yahoo.  That's kind of my junk email account, but I do still check it regularly.  Like I said, I have a ton of projects, but I tend to gravitate towards the ones that generate the most interest, so if you start emailing me twice a week asking for updates I might actually get around to it 

Also, I did mod a USA Red version, but I only played it through the title screen (it was a mod for a friend, and I only tested so far as to confirm the game booted, naively believing that it would work consistently after that...).  To be honest, the only game I've played for any length of time with the mod is Zelda DX, which is also MBC5... so maybe MBC3 doesn't work, but it's weird because stuntpenguin claimed the FM28V020 worked fine, and it uses the same input latching   However, if I can test it out to confirm my suspicions, it may still be possible with the glue logic I posted above...


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## loco365 (Mar 17, 2014)

I'm actually really curious as to whether this will work. I have a Japanese Crystal, however, the doofus that "repaired" it, shorted out the save chip, so it cannot save anymore. If I can replace the save chip with one of these, I'd gladly order one and replace it.


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## Dym (Jul 23, 2014)

I have a few European Red, Yellow and Blue carts that are all MBC5, will the FM18W08 chip work with them? Thanks!


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## yafeee (Jul 23, 2014)

Dym said:


> I have a few European Red, Yellow and Blue carts that are all MBC5, will the FM18W08 chip work with them? Thanks!


 
Yes, it will work !


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## Notanyonewhocares (Jul 26, 2014)

FM18W08 can be purchased here hurry: http://www.ebay.com/itm/FM18W08-SG-...511?pt=LH_DefaultDomain_0&hash=item4174da093f


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## qlb1234 (Jan 19, 2017)

Sorry to bump an old thread.
To anyone who's still wondering whether there's a solution, the short answer is "probably yes".
TL;DR: You can probably replace the SRAM on a genuine Pokemon Gold cartridge with an FM28V020.

The main reason, as stated by qwertymodo at #11, and by BennVenn here, is that FM1808 (or other variants) doesn't support continuous read. Section "Pin Definitions" on Page 3 states that,



> Chip Enable: The device is selected when CE is LOW. Asserting CE LOW causes the address to be latched internally. Address changes that occur after CE goes LOW will be ignored until the next falling edge occurs.



Loud and clear. This feature - multiple read operations in one cycle of /CE - is a feature of majority SRAM chips, e.g. W24257. Rabby250 at #12 listed some Pokemon games which won't work with FM1808:

Yellow in Japanese region
Red/Blue in US region
Gold/Silver in any region
Crystal in any region except Japanese
They're all newer Pokemon games (except that OP tried it on European version of Yellow, which was released in 2000, still works), as opposed to Pokemon Red & Green. So the wild guess "they continuous read RAM" may very likely hold true. But I can't imagine how this flaw introduces graphic glitches.

The new generation of Cypress FRAM, whose name starts with "FM2", is capable of doing this. In fact, they even support continuous write, which is amazing if you're making a homebrew flash cart.

The reason I kept using the word "probably", is that I have yet to try an FM28V020 on a Pokemon Gold cart. I bought a used one for this yesterday but it's still on the way. I managed to replace the SRAM on my EMS 64M cart with a FM28V100 and I didn't get the glitch OP has encountered. I will order some FM28V020 and update as soon as possible. And for people who can't wait, just go for it.

Update: Don't do it. It doesn't work.
I was experiencing graphic glitch after replacing the original RAM with FM28V020. After I saved the game, the save file doesn't persist through reboot.

Maybe we should wait for yet another generation of FRAM chip, the one which will be truly functional identical to static RAM.

Original components: http://i.imgur.com/WwXf6rk.jpg

Graphical glitch:
http://i.imgur.com/S5gGNuN.jpg
http://i.imgur.com/u8RfDKo.jpg

Saving:
http://i.imgur.com/tUrvvye.jpg


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## wolffangalchemist (Feb 20, 2017)

I was getting this issue bad on my mod i just did tonight but figured it out, i connected pin 20 (CE) directly to the ramcs pin on mbc5, works for pokemon yellow with mb85r256s Fram chip i (pulled from a dead gba game.)  someone might want try it with these.
http://reinerziegler.de/mbc5.gif


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## willis936 (Feb 21, 2017)

Thanks for that post qlb.  That explained a problem I ran into after dumping $30 on a flasher and $45 on a flashcart from tindie.  Non volatile saving is a nice to have.  Having things actually work is a must have.


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## aldighieri (May 7, 2017)

Sry to bump this topic, but i have 3 GBC pokemon carts that dont use bat and save with no problem, look the pic.







Im looking for more pkm carts like this one, but i cant find. I need to check if the clock on Gold version is working, but i think its not.


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## koffieleut (May 7, 2017)

Are you sure those are gbc carts? I can remember that there are a lot of more components around the battery.


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## Sliter (May 7, 2017)

this ideia is very awesome, I haven't a clue that could work that way 
(only bootlegs that actually have a different cart structure, and they do for GBA games nowadays, but not for GB/c I think? )
but pokemon GS don't need to have a battery anyway? because of the clock ?
I Have a pirate pokemon crystal that don't have clock and it have some wreinds bugs... not sure if is for differnte " circuit" issues or by being a fake XD


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## aldighieri (May 7, 2017)

koffieleut said:


> Are you sure those are gbc carts? I can remember that there are a lot of more components around the battery.


Yes GBC carts, this one dont use battery, i think the black drop is a F-RAM. Nowadays the board is smaller.


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## Sliter (May 7, 2017)

aldighieri said:


> Sry to bump this topic, but i have 3 GBC pokemon carts that dont use bat and save with no problem, look the pic.
> 
> 
> 
> ...


wich games are these? Pokemon?
Threse are repro anyway, that solved my question above about fake gbc games without battery :v  almost sure the clock don't work on GS threse... there not even the clock thing on the board


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## aldighieri (May 7, 2017)

Sliter said:


> wich games are these? Pokemon?
> Threse are repro anyway, that solved my question above about fake gbc games without battery :v  almost sure the clock don't work on GS threse... there not even the clock thing on the board



Poke Gold, Green and Red. The Gold dont have the clock working. You know how to repro this carts?


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## Sliter (May 7, 2017)

aldighieri said:


> Poke Gold, Green and Red. The Gold dont have the clock working. You know how to repro this carts?


how to not actually, they make black chip like these and burn the rom on them with a machine xD
Gold don't work clock because of the clock thing (and a battery to feed that), I don't think this can be made working unless the circuit have the feature for that ...




the clock thing is that with white tape on the on the top left  of the board 

Btw, do they work with pokemon stadium? I'm curious XD


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## yafeee (May 15, 2017)

Hello, glad to see there is still an interest for this mod 

Funny that you mention Pokemon Stadium. I'm still using my modded Pokemon Blue and Yellow, but recently discovered that they are now *not compatible* with Pokemon Stadium.


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## Sliter (May 15, 2017)

yafeee said:


> Hello, glad to see there is still an interest for this mod
> 
> Funny that you mention Pokemon Stadium. I'm still using my modded Pokemon Blue and Yellow, but recently discovered that they are now *not compatible* with Pokemon Stadium.


why? 100% incompatible? I remember by using pirates they may not be able to play or get a team, but could use the pokes on the minigames :v 
maybe they check the batteries or something? lol


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## migles (May 15, 2017)

yafeee said:


> Hello, glad to see there is still an interest for this mod
> 
> Funny that you mention Pokemon Stadium. I'm still using my modded Pokemon Blue and Yellow, but recently discovered that they are now *not compatible* with Pokemon Stadium.


interested in this as well, but with gen 2 there is the clock problem..
do anyone know if there a mod to put a rechargeable battery and charge system in the card? probably it's complex but i do think it's possible...


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## Rabby250 (May 29, 2017)

Well, it's good to see someone else interested in this subject!

I've been giving up on trying for a while so here's a wrap-up for those who were still trying:

Our previous attempt was to find a non-volatile drop-off replacement for the SRAM chip on genuine Pokémon carts so that the carts can save without batteries.
(Sorry aldighieri, your carts were repro carts, which were not official Pokémon carts and thus not related to the discussion. Official Pokémon carts don't have glob tops.)

Every Game Boy cart has a chip called MBC. In Pokémon carts, there are 4 different types of MBC:

MBC1: the oldest MBC which could be found on early titles
MBC3: the MBC introduced between MBC1 and MBC5; in addition, MBC3 was required for most games with real-time clock (RTC) features
MBC5: the latest MBC which could be found on titles released near the end of GBC's lifecycle
MBC30: a special type of MBC found only on Japanese Crystal for RTC and large RAM support
A table of which Pokémon cart comes with which MBC is shown below:

```
R/G/B   Yellow  G/S     Crystal

Japanese  MBC1    (MBC3)  (MBC3)  [MBC30]

English   (MBC3)  MBC5    (MBC3)  (MBC3)

European  MBC5    MBC5    (MBC3)  (MBC3)
```

The problem we had run into was that while there exist some known FRAM chips (FM1808-70, FM1808B and FM18W08) which in theory could be the replacements we're looking for, our installation attempts showed that they only work on MBC1 and MBC5 carts, and will result in graphic glitches and save failures on MBC3 carts.

Since most of the Gen II games come with MBC3, this means that we have yet to find a replacement for the Gen II games. We'll either have to find other replacements or install additional circuits instead of just a drop-off.
(Note: Japanese Crystal is out of the question since its RAM was 4x larger than other games and no replacements are available.)

Hope this explains the situation we're in.


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## OfficialFBomb (May 30, 2017)

Just wanted to mention the original OP listed to use the  FM28V020 and lift the top right pin.. Thats why it worked with Gold, you used the FM18W08 which is why it worked with Yellow, they are somewhat identical but somewhat not.. The last poster was not the OP posting..

But who knows, i was planning to order an 08 and 20 but i keep finding ones with a -sg or -pg and idk if there the same or not


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## Sliter (May 30, 2017)

I see that nobody care much about working with pokemon stadium (well maybe I care too much? hhaha could be because was something I wanted much as kid and never got?:B hahaha )
BUt this could be by the fact that there are no batery? if you use the non volatility save thing but have a battery, it could work? or because the save structure?

(not that I have much to do more than curiosity... I just have an japanse silver that I changed the battery recently but never really got it to play lol more than this, a pirate crystal full of bugs XD )


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## Rabby250 (Jun 10, 2017)

OfficialFBomb said:


> Just wanted to mention the original OP listed to use the  FM28V020 and lift the top right pin.. Thats why it worked with Gold, you used the FM18W08 which is why it worked with Yellow, they are somewhat identical but somewhat not.. The last poster was not the OP posting..
> 
> But who knows, i was planning to order an 08 and 20 but i keep finding ones with a -sg or -pg and idk if there the same or not



The reason we're trying the FM18 chips was that the maximum voltage of FM28V020 does not match PCBs of Gameboy carts, and will require some extra work (e.g. lift pin) instead of just a drop-off.
Since the FM18 chips works under the same voltage as Gameboy carts, they were considered "theoretically" as drop-off replacements - until we tried and found out it wasn't the case in MBC3s.



Sliter said:


> I see that nobody care much about working with pokemon stadium (well maybe I care too much? hhaha could be because was something I wanted much as kid and never got?:B hahaha )
> BUt this could be by the fact that there are no batery? if you use the non volatility save thing but have a battery, it could work? or because the save structure?
> 
> (not that I have much to do more than curiosity... I just have an japanse silver that I changed the battery recently but never really got it to play lol more than this, a pirate crystal full of bugs XD )



Stadium 2 (U/E) and Stadium GS (J) apply non-volatile saves by default, so I guess that's the reason why they're not mentioned in NVRAM modification threads.
(So yes, players could at least deposit all their rare Pokémon and items into Stadium 2 to exclude those from possible data loss.)

Sorry I couldn't understand your last question, but as non-volatile saves do not rely on batteries to keep the data, the issue shouldn't be related to having a battery installed or not.
(That's why we're doing the NVRAM mods - you won't loss your save when the battery runs out. We still need a battery to run the clock, but that should be the only thing which needs a battery.)


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## Sliter (Jun 10, 2017)

Rabby250 said:


> The reason we're trying the FM18 chips was that the maximum voltage of FM28V020 does not match PCBs of Gameboy carts, and will require some extra work (e.g. lift pin) instead of just a drop-off.
> Since the FM18 chips works under the same voltage as Gameboy carts, they were considered "theoretically" as drop-off replacements - until we tried and found out it wasn't the case in MBC3s.
> 
> 
> ...


That I understood before, these GS with save type  mod weren't working on the stadiums, but now you told me that works and stuff ... so I'm not sure :v


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## JS7777 (Aug 2, 2017)

Hello,

Sorry to bump this post but it will be cool to fix this problem.

So, i bought a FM16W08 and i've installed it in a gameboy game : Wario Land Super Mario land 3 (MBC1 and 64kbit sram)

I've uploaded a 100% save in the cartridge.

Tried on my gameboy and works but then i got some glitches. "Wario" is invisible, impossible to play.

So i found this topic 3 month earlier and i decided to post here today.

I've contacted BeenVenn,  if you don't know him check his shop https://bennvenn.myshopify.com.
He makes cartridges with fram chips but later i've noticed he makes his own mbc chip.

I've explained the problem and he told me to try to multipex the /CE signal with the cartbus /CLK signal. I've tried with a CD4011, didn't work, black nintendo logo. In the process i've swapped pin 1 and 3 by mistake so this could have damaged the MBC1.






Later on i found this :
https://www.reddit.com/r/Gameboy/comments/4rkoyz/bennvenns_gbgbc_high_quality_reproduction_pcb/

In a post BeenVeen says :


> RAMTRON brand FRAM has an unusual requirement where the /CE line must be strobed before any read or write in order to 'precharge' the magic within, and update the address matrix (It's all in the datasheet). On the older GB ROM's the gameboy does single byte reads and writes which due to the nature of the GB bus the /CE line automatically strobes.
> 
> The GBA is a little lazy in this regard and holds the /CE line low and just increments the address bus. On a real ROM/SRAM this is a legitimate way of reading data (assuming you adhere to timings) but with the FRAM it simply repeats the same data from the address where the /CE line first became active.
> 
> ...



Could be great if someone tries to multiplex /CE and /CLK cartbus, even if i already did. (My cart could be damaged)

I'm gonna buy a Logic analyser soon...


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## JS7777 (Aug 14, 2017)

*Update :*
I've installed the FM16W08 in a homemade flash cart with an mbc5 and a am29f080b.
Every game i've tested works without glitches and save functionality works *expect* Wario Land Super Mario land 3. (Save works but it's impossible to play, invisible character)
I have no idea why...


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## Sliter (Aug 14, 2017)

JS7777 said:


> *Update :*
> I've installed the FM16W08 in a homemade flash cart with an mbc5 and a am29f080b.
> Every game i've tested works without glitches and save functionality works *expect* Wario Land Super Mario land 3. (Save works but it's impossible to play, invisible character)
> I have no idea why...


maybe rom glitch? õ3o try other dumps/region

how is a homemade flashcard? o-o


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## JS7777 (Aug 14, 2017)

queendude said:


> I Poop on your NTR


What ?



Sliter said:


> maybe rom glitch? õ3o try other dumps/region


Will try



Sliter said:


> how is a homemade flashcard? o-o


http://www.reinerziegler.de/download/MBC5_Cart.pdf


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## Sliter (Aug 14, 2017)

JS7777 said:


> http://www.reinerziegler.de/download/MBC5_Cart.pdf


Maaaaaaan It would hut me so much  killing a zelda game  ( almost got an extra oracle one time but at last I could not :v)
by the color must be an awakening DX? I don't have this yet...
Also could be added the clock stuff for the GS pokemon or need to be done to a acutall GS pokemon board?

Maybe I would ask someone to do one like this for me, not sure if I can by myself ... I was wanting for future pokemon hack/translation plans ...

Also how to write the rom to it?

I almost got one like this one time because I heard we could write any games to it, but the guy wanted too much for what I had that time xD

Also I heard that the new bootlegs can be re-flashed, both GBA and GB/c ones, O wonder what kind of device I need, if this is true ...


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## JS7777 (Aug 15, 2017)

Sliter said:


> Also I heard that the new bootlegs can be re-flashed, both GBA and GB/c ones, O wonder what kind of device I need, if this is true ...


Yea some can be reflashed, for the gameboy a simple gb programmer, you can make one yourself.
For the gba botlegs i'm currently working on a programmer, gba botlegs can be reprogrammed with the parallel cable that was include in the firelinker 128m.


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## Sliter (Aug 15, 2017)

JS7777 said:


> Yea some can be reflashed, for the gameboy a simple gb programmer, you can make one yourself.
> For the gba botlegs i'm currently working on a programmer, gba botlegs can be reprogrammed with the parallel cable that was include in the firelinker 128m.


so not sure if I look for a flasheable bootleg, the GB "memory" or mod one cart myself/ask someone for doing it? xD
This GB programmer could work for gba with the program? maybe not?
I heard about an USB-GBA cable that could reprogram the bootleg, and looks like we could not DIY it...
I'm wanting to do all he stuff but I have no idea where to start XD

Can't we use an DS/DSlite to do the job? the EZFlah 3in1 had a way to send the rom to it, maybe a  homebrew could do the job (for GB/C games maybe work, but it would need to put the circuit there without the case? hahah)


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## JS7777 (Aug 15, 2017)

Sliter said:


> the GB "memory" or mod one cart myself/ask someone for doing it? xD


You can make one your own but you need some soldering skills, i don't mind making one for you but i need a cartridge, if you want the clock feature you need a pokemon one.



Sliter said:


> I heard about an USB-GBA cable that could reprogram the bootleg, and looks like we could not DIY it...


Where did you hear that ?



Sliter said:


> Can't we use an DS/DSlite to do the job? the EZFlah 3in1 had a way to send the rom to it, maybe a homebrew could do the job (for GB/C games maybe work, but it would need to put the circuit there without the case? hahah)


Didn't find anything


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## Sliter (Aug 15, 2017)

JS7777 said:


> You can make one your own but you need some soldering skills, i don't mind making one for you but i need a cartridge, if you want the clock feature you need a pokemon one.


well I have a bit that I'm not that trustful (but I saved a crazy "corroded" N64 controler XD McGuiver must be proud!) haha I heard that the "GB Memory" the board have a place for the clock thing ... but anyway depending your price we can see what we can do o3o


JS7777 said:


> Where did you hear that ?


was in a post about re flashing an zelda minish cap bootleg that come with a save problem
The cable was from a flahscard that the one you told, but instead of parallel port, was by the USB
Edit: Found it (at least wich was)





Flash2Advance USB linker



JS7777 said:


> Didn't find anything


about this cart?
here:
https://gbatemp.net/threads/beginners-guide-to-the-ez-flash-3in1.293643/
but well, this cart was made to work like this xD but I've never tried this GBAexplorer with a bootleg (because I'm without a DSlite at the moment :v )


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## JS7777 (Aug 15, 2017)

Sliter said:


> well I have a bit that I'm not that trustful (but I saved a crazy "corroded" N64 controler XD McGuiver must be proud!) haha I heard that the "GB Memory" the board have a place for the clock thing ... but anyway depending your price we can see what we can do o3o


GB Memory ?



Sliter said:


> was in a post about re flashing an zelda minish cap bootleg that come with a save problem
> The cable was from a flahscard that the one you told, but instead of parallel port, was by the USB
> Edit: Found it (at least wich was)


That cable can't be find for sell on internet. A shame.
Do you have the link of that topic ?



Sliter said:


> about this cart?
> here:
> https://gbatemp.net/threads/beginners-guide-to-the-ez-flash-3in1.293643/
> but well, this cart was made to work like this xD but I've never tried this GBAexplorer with a bootleg (because I'm without a DSlite at the moment :v )


I know this cart, what i mean is that i didn't find any homebrew for flashing a gba botleg.
GBAexplorer will work only with the ez flash 3in1.


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## migles (Aug 15, 2017)

@qlb1234 @JS7777 @yafeee @Rabby250 @qwertymodo

what's the conclusion about this project?
can we finally mod original cartridges of pokemon gen 1 and 2 with non volatile memory?

can i purchase pre modded games from any of you?
are theese games working with poke stadium? what about super game boy mode in the first gen?


there was a kinda similar project that was putting a battery holder compartment to easily swap the batteries, but used smaller ones which are more cheaper..
but replacing the s-ram would be even better...


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## JS7777 (Aug 15, 2017)

migles said:


> what's the conclusion about this project?
> can we finally mod original cartridges of pokemon gen 1 and 2 with non volatile memory?


Looks like yea but you won't get the clock function or you must leave the battery.



migles said:


> can i purchase pre modded games from any of you?
> are theese games working with poke stadium? what about super game boy mode in the first gen?


I don't have any games but i can do it for you if you want a game with a fram chip. I will need the name of your games though
pokemon stadium ?? super gameboy mode ??


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## qwertymodo (Aug 15, 2017)

I never got around to debugging the GS glitching (unless it was just the RTC, in which case you can still swap the RAM, just keep the battery too, if it dies the clock stops but you won't lose your save). What I CAN say for sure is that Gen 1 works.

Sent from my m8wl using Tapatalk


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## migles (Aug 15, 2017)

JS7777 said:


> Looks like yea but you won't get the clock function or you must leave the battery.


that's obvious...
my point is to prevent save losing.. however the easily swapable battery holder mod + backup tool is another solution i am thinking..
or, :why not both:  mod the cartridge both with the F-RAM chip and easily swapable battery, when clock battery dies, save is not lost, replace battery clock working again



JS7777 said:


> I don't have any games but i can do it for you if you want a game with a fram chip. I will need the name of your games though
> pokemon stadium ?? super gameboy mode ??



yeah, it was kinda mentioned in previous posts that doing this non volatile f-ram mod will prevent the cartridge from working with pokemon stadium (n64 transfer pack) which is a big bummer
by super game boy mode i mean, will the cartridge work without issues in color in a snes ? it was also mentioned some sprites corruption in other games, kinda worried this mod will glitch in super game boy mode


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## Sliter (Aug 15, 2017)

JS7777 said:


> GB Memory ?







this thing



JS7777 said:


> That cable can't be find for sell on internet. A shame.
> Do you have the link of that topic ?


yeah :/ I don't find the topic yet but if I do, I send you
but there wasn't much info more than saying it's was possible, if I'm correct



JS7777 said:


> I know this cart, what i mean is that i didn't find any homebrew for flashing a gba botleg.
> GBAexplorer will work only with the ez flash 3in1.


oh right xD yes I know nobody did(or made public), just speculating if is possible.



JS7777 said:


> I don't have any games but i can do it for you if you want a game with a fram chip. I will need the name of your games though
> pokemon stadium ?? super gameboy mode ??


I think is about it not having problem (working like oficial) when linking to Pokestadium and snes GB player


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## migles (Aug 15, 2017)

qwertymodo said:


> What I CAN say for sure is that Gen 1 works.


but is the pokemon stadium compatibility issue solved?


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## qwertymodo (Aug 15, 2017)

Sorry, I hadn't really kept up on this thread so I missed that part. It sounds like what has to happen is to add the logic on the /CS pin. There's one option listed earlier in this thread, but the one once used instead on SNES games instead is CS_OUT = CS OR (RD AND WR) which can also be done with a quad NAND, i.e. CS_OUT = (CS NAND CS) NAND (RD NAND WR). The wiring is likely to be tricky, unfortunately...

Sent from my m8wl using Tapatalk


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## Sliter (Aug 16, 2017)

JS7777 said:


> Didn't find anything


oh I found this , but was also kinda of a request:
https://gbatemp.net/threads/reflashing-bootleg-gba-games.469792/


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## Tooom (Sep 8, 2017)

I know a search for components on the site, and I often use it and hope to help you
findic.us/?lnk=lt


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## wadeVillines (Oct 17, 2017)

Would it be possible to make the FM18W08 work for MBC3 cartridges using this added logic?
!(WR AND RD) AND A15 = FRAM CE

We know ROM is enabled on A15.
We know ROM shares the bus with RAM.
So, as long as a read or write is taking place, and it is NOT the rom, it should be the ram? We could then maybe OR the read and write signals, then AND that with the inverse of A15? Finally, invert it because CE of FM18W08 is active low.

I'm really sorry to bump this thread after all this time, but I have invested a lot of time and money to this project, and I think I'm very close to finishing it. I have made a couple prototype flash cartridges with MBC3 and FRAM, and everything works except communicating with my FRAM chip. See for yourself in the attached pictures.


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## gonzaloj (Feb 19, 2018)

Hi, thanks for all, I need some help,
The conclusion that i want to apply to my games are:
Zelda Dx/Pk red and blue FmFM18W08 
Pkmn crystal FM28v020
Zelda Oracle of ages/seasons FM16W08
This chips are allright for this games?
Whats the diferences between soic And a sop chip?

--------------------- MERGED ---------------------------



gonzaloj said:


> Hi, thanks for all, I need some help,
> The conclusion that i want to apply to my games are:
> Zelda Dx/Pk red and blue FmFM18W08
> Pkmn crystal FM28v020
> ...


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## gonzaloj (Feb 20, 2018)

Thanks?


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## JS7777 (Feb 25, 2018)

gonzaloj said:


> Hi, thanks for all, I need some help,
> The conclusion that i want to apply to my games are:
> Zelda Dx/Pk red and blue FmFM18W08
> Pkmn crystal FM28v020
> ...



I won't be able to tell you if it will work but you can give it a try, I've checked the pins and size compability, if it doesn't work or there is some glitch then connect the Vdd pin and CE pin with a 10K resistor.


Same pin spacing for SOP AND SOIC but SOIC got a wider package. Check their datasheets for more info.


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## wadeVillines (Feb 27, 2018)

Hey guys, sorry for bumping this thread, but I think I just cracked the case.

The FM18W08 is the chip you want, should work on any cartridge that has SRAM.
If you are using MBC3, connect the FRAM CE pin directly to the cart CS pin (pin 5) instead of the RAMCS pin on the MBC3. Leave the RAMCS pin on the MBC3 disconnected.
If you are using MBC5, this chip can be used as a drop-in replacement with no additional work.
*ONLY ON MBC5:*
The power-down chip can be removed if you place a 10K resistor between the Vcc and CE pin of the FRAM.

EDIT: Unfortunately this method only works for Gameboy Color, not DMG. Games on the DMG do not boot if RAM isn't connected to the MBC3 RAMCS pin. I have a feeling it has to do with the GBC running at 2x the speed, but I can't say for certain. This will take more work to figure out.


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## gonzaloj (Mar 2, 2018)

wadeVillines said:


> Hey guys, sorry for bumping this thread, but I think I just cracked the case.
> 
> The FM18W08 is the chip you want, should work on any cartridge that has SRAM.
> If you are using MBC3, connect the FRAM CE pin directly to the cart CS pin (pin 5) instead of the RAMCS pin on the MBC3. Leave the RAMCS pin on the MBC3 disconnected.
> ...


You can put photos? I dont understand all the steps because im not a good tecnicia.
The only for mbc 5 step is for all the games?


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## wadeVillines (Mar 5, 2018)

gonzaloj said:


> You can put photos? I dont understand all the steps because im not a good tecnicia.
> The only for mbc 5 step is for all the games?



Yes, if you are using an MBC5, you should be able to just remove the RAM chip and place your FRAM. Removing the power-down chip is optional, but you can do it if you connect one end of a 10k resistor to the VCC pin of your FRAM and the other to the CE pin of FRAM. The resistor trick is totally optional, so you don't have to do it unless your power-down chip is dead or something. Honestly, it's only really useful if you're building a flash cartridge from scratch.


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## wadeVillines (Mar 7, 2018)

Hey all, hopefully this is it. Figured out how to get the FM18W08 chip to work on both Gameboy DMG and Gameboy Color, which means it should theoretically work on the GBA as well.

For this to work, you will need to OR together these signals:
-/RAMCS from the MBC3
-CLK from the cartridge slot

The output of this OR should go to the /CE of your FRAM. Basically, if any one of these signals goes high, then /CE should also go high (inactive).

Originally, I was using a 3-input OR (RAMCS, CS, CLK), but it's a little bit overkill I think. CLK is already rising and falling every cycle, so CS isn't really needed as far as I know.

*EDIT*: use a 2-input OR instead of 3 (RAMCS and CLK), use that output as your FRAM /CE signal.


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## JS7777 (Mar 7, 2018)

Great.

I made a post a while ago about that, and bennvenn told me to use with a nand gate.

By using a OR gate it will probably fix my glitch issue with Wario Land cartridge.

My post :



JS7777 said:


> So, i bought a FM16W08 and i've installed it in a gameboy game : Wario Land Super Mario land 3 (MBC1 and 64kbit sram)
> 
> I've uploaded a 100% save in the cartridge.
> 
> ...


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## gonzaloj (Mar 7, 2018)

wadeVillines said:


> Hey all, hopefully this is it. Figured out how to get the FM18W08 chip to work on both Gameboy DMG and Gameboy Color, which means it should theoretically work on the GBA as well.
> 
> For this to work, you will need to OR together these 3 signals:
> -/CS from the cartridge slot
> ...


But you say before that you only hace to put the Fram fm18w08 in the Game, in What games i have to do It? Works with all mbc?


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## wadeVillines (Mar 7, 2018)

gonzaloj said:


> But you say before that you only hace to put the Fram fm18w08 in the Game, in What games i have to do It? Works with all mbc?



In MBC5, you only have to place your FM18w08. In MBC3, you will have to OR those signals together and send the output to your FRAM /CE pin.

--------------------- MERGED ---------------------------



JS7777 said:


> Great.
> 
> I made a post a while ago about that, and bennvenn told me to use with a nand gate.
> 
> ...


Wow, that post takes me back. I think I remember reading over that a looong time ago, back when I was doing my initial research and knew almost nothing.
I believe you are right, I'm 99% sure that Wario game has the same issue as Super Mario Land 2, using part of RAM as system RAM. 

I need to edit my post, but I think this solution can be simplified to match what you have there. A 3-input OR doesn't seem necessary, and a 2-input OR using only CLK and RAMCS seemed to do the trick for me.
And because using an OR on those signals fixed the sprites in SML2, I'm hoping it will work for you as well.


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## gonzaloj (Mar 8, 2018)

wadeVillines said:


> In MBC5, you only have to place your FM18w08. In MBC3, you will have to OR those signals together and send the output to your FRAM /CE pin.
> 
> --------------------- MERGED ---------------------------
> 
> ...


you can upload some photos of the mbc 3 method? 
P.D: thanks for all your discoveries, you are a amazing gamer!!!


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## wadeVillines (Mar 9, 2018)

Just tested with Pokemon Prism. You will need to OR together CS, RAMCS, and CLK for this game to completely work. Without CS, the save file will corrupt and all in game sprites will have issues. Without RAMCS, the clock data on the continue screen does not update (it is supposed to update every second). There are probably more issues caused by not including RAMCS, but that is all I have found with my short tests. So, to be safe for full compatibility, I would OR together all 3 signals.

Also, I added a quick doodle of the setup. I will get around to a more detailed explanation later on. I hope to start up a blog after I design and assemble a working cartridge.


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## JS7777 (Mar 9, 2018)

What Or gate you recommend ? (number ?)

Thanks


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## wadeVillines (Mar 9, 2018)

JS7777 said:


> What Or gate you recommend ? (number ?)
> 
> Thanks


I haven't tried out any of them (I just used some diodes to rig an OR gate), but I just bought these:
https://www.digikey.com/product-detail/en/texas-instruments/SN74LVC1G332DCKR/296-15943-6-ND/1849509

It will take a few days for them to arrive, but I don't see any issues with them. They had the shortest delay I could find at only 4.5ns and accept anywhere from 1.7V to 5V.

Using the 2-input one seemed to work for every game besides Pokemon Prism, which is doing something differently. I don't know why adding the CS line fixes it, because the RAMCS signal is specifically there for signaling the RAM. If I was more ambitious, I would dig into it and try to find out. It might be possible to patch the game to not need that extra signal, but I wouldn't know for sure. Probably more work than it's worth anyway.


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## gonzaloj (Mar 28, 2018)

Hi! I I send a picture of Pkmn crystal structure todo a cypresssemiconductors worker, he say that a Fram memory FM1808B-SG in theory works with Pokemon crystal And maybe with other mbc3


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## Deleted User (Apr 14, 2018)

gonzaloj said:


> Hi! I I send a picture of Pkmn crystal structure todo a cypresssemiconductors worker, he say that a Fram memory FM1808B-SG in theory works with Pokemon crystal And maybe with other mbc3


Unfortunately, according to that chip's datasheet, it has the same problem as the FM18W08. "Unlike an SRAM, changing address values will have no effect on the memory operation after the address is latched."


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## gonzaloj (Apr 23, 2018)

I Tell the problem to a cypress worker And he wrote a datasheet with all the information about replacing the sram memory of pkmn crystal. This is the download link:
http://www.cypress.com/file/125216/download


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## wadeVillines (Apr 24, 2018)

Just a small update: I completed my PCB and have been enjoying playing Pokemon Prism on it. Turns out the OR gate only needs two inputs: Clock and RAM_CS. Every game I've played on it works like a charm. Been playing it on Pokemon Stadium as well. By changing the header file of the ROM to a Pokemon ROM header, any game can be played on Pokemon Stadium's GB Tower (using the Transfer Pak).


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## JS7777 (Apr 24, 2018)

Great to hear that it worked !


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## wadeVillines (Apr 26, 2018)

Something interesting, however. I made 2 versions of this cartridge: 1 uses 3 inputs for its OR gate (CLK, RAM_CS, CS) and the other uses only 2 (CLK and RAM_CS). Commercial cartridge programmers, such as the one from J. Rodrigo, cannot program my RAM chip if it is using 2-input OR. This made me realize that these programmers don't use the CLK pin for anything at all. So, without the CS pin, the FRAM isn't getting toggled correctly. This can be fixed one of two ways: using the 3-input OR gate, or connecting the CLK pin to the CS pin on the programmer.

Note that this won't matter for MBC5 carts, since they don't use the CLK pin, either. This ONLY applies to MBC3. After this modification to the programmer, it will still work for both types, though.

One MORE thing! I didn't understand why Pokemon Red/Blue used MBC3 if they have no RTC (I thought maybe MBC5 just wasn't developed yet). However, the MBC3 has a clock input pin (system clock, not RTC clock) while the MBC5 does not. I believe this chip was used so these games could be run in double or triple speed mode when playing on Pokemon Stadium, using Doduo and Dodrio mode, respectively. Just an interesting tidbit.


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## Deleted User (May 14, 2018)

wadeVillines said:


> ...  (I just used some diodes to rig an OR gate) ...


I'm assuming this is with all the cathodes going to the F-RAM, do I need any pullup/pulldown resistor when doing it with diodes? And will this mod still allow the RTC to work correctly (from the battery)?


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## wadeVillines (May 17, 2018)

Teki5 said:


> I'm assuming this is with all the cathodes going to the F-RAM, do I need any pullup/pulldown resistor when doing it with diodes? And will this mod still allow the RTC to work correctly (from the battery)?



Yes, it has been a while since I did this, but I remember using a 10K pulldown resistor between the diode output and ground.


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## Fishaman P (May 17, 2018)

Very interested in a writeup/blog post with pictures!


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## JS7777 (May 19, 2018)

Fishaman P said:


> Very interested in a writeup/blog post with pictures!


I would be able to do it when I get the parts and time.


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## Deleted User (May 20, 2018)

wadeVillines said:


> Yes, it has been a while since I did this, but I remember using a 10K pulldown resistor between the diode output and ground.


Alright, I'll try that! I just soldered it up without the pulldown and I get dark striped square sprites.
UPDATE: It works perfectly, however... My intention here is to still have a battery, for the clock, and when that runs out I can replace it without worrying about my save. With the 10K pulldown, and a standby output from the diodes of about 2.2v... That's drawing 220μA. Not a lot for a running console, but the battery I'm using (80mAh) will only last about two weeks. And that's before I even consider the F-RAM standby current. Looks like I'm better off getting one of those OR-gates after all


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## wadeVillines (May 22, 2018)

Teki5 said:


> Alright, I'll try that! I just soldered it up without the pulldown and I get dark striped square sprites.
> UPDATE: It works perfectly, however... My intention here is to still have a battery, for the clock, and when that runs out I can replace it without worrying about my save. With the 10K pulldown, and a standby output from the diodes of about 2.2v... That's drawing 220μA. Not a lot for a running console, but the battery I'm using (80mAh) will only last about two weeks. And that's before I even consider the F-RAM standby current. Looks like I'm better off getting one of those OR-gates after all


Lol, yeah I've got some great OR gates that draw about 4 micro amps and it works great. But hey, you can run the FM18W08 chip on system power (5v) instead of on battery. It doesn't need constant juice to work. If you're worried about your clock data, don't: the clock data is stored completely on MBC3, so this is the only chip that needs to be battery powered. For safety, you can use a 10K pullup resistor between #CE and VCC of your FRAM to make sure it only gets enabled when it's supposed to.

--------------------- MERGED ---------------------------



Fishaman P said:


> Very interested in a writeup/blog post with pictures!


It's on the way! I actually just bought a web domain to host it, and am typing up a bare-bones HTML site as we speak. I'll link you when it's ready to host.
EDIT:
The website is ready, but it is far from complete. You can find the gerber files for my board design, a parts list, as well as some other information related to the project. 

Website is RetroReboot.net, it's about as simple as it gets, but I'm learning HTML as I go.


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## Deleted User (May 23, 2018)

wadeVillines said:


> Lol, yeah I've got some great OR gates that draw about 4 micro amps and it works great. But hey, you can run the FM18W08 chip on system power (5v) instead of on battery. It doesn't need constant juice to work. If you're worried about your clock data, don't: the clock data is stored completely on MBC3, so this is the only chip that needs to be battery powered. For safety, you can use a 10K pullup resistor between #CE and VCC of your FRAM to make sure it only gets enabled when it's supposed to.


I've ordered some OR gates and waiting for them to arrive. I'll just run the save chip and the OR gate both from system power. The gate should isolate the signals, so if the MBC is still holding one of those signals high, the FRAM won't be able to draw power through CE. I'm assuming none of the address lines are held high by the MBC without system activity?
The clock data thing is a bit obvious now I think about it. For some reason I had in my head that powering the save chip from battery had the secondary purpose of regularly updating the stored time or something, but I suppose that would drain the battery extremely fast!

Update: I've been waiting for those OR gates but apparently I never actually went to checkout...
Update2: They arrived and apparently the product image was wrong AND I misread the details so I ended up with microscopic chips I have no hope of soldering. Third time lucky?


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## gonzaloj (Jul 5, 2018)

With mbc 5 i only have to replace And with mbc 3 i have to replace And OR ramcs And clk with output ce Signal.
 But with mbc 1 And GBA? And What OR Gate i have to use?


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## gonzaloj (Jul 5, 2018)

With mbc 5 i only have to replace And with mbc 3 i have to replace And OR ramcs And clk with output ce Signal.
 But with mbc 1 And GBA? And What OR Gate i have to use?


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## wolffangalchemist (Oct 5, 2018)

EDIT:
figured it out, wired it up, fired it up, and was very pleased.
i used aMB85R256 F-ram chip instead of a FM1808 either should work.
images for those who need would like to give it a go and showing it working.







gif video i uploaded of it working.
https://i.imgur.com/AgNWEL8.gifv



Spoiler: images and video/gif


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## yafeee (Oct 10, 2018)

wolffangalchemist said:


> EDIT:
> figured it out, wired it up, fired it up, and was very pleased.
> i used aMB85R256 F-ram chip instead of a FM1808 either should work.
> images for those who need would like to give it a go and showing it working.
> ...



Awesome !

Edit: tried this weekend with a FM18W08, it works perfectly :3

Thanks a lot for following up, I will add your fix to the first post !


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## famiac (Dec 9, 2020)

PSA: If you replace your SRAM with FRAM (FM18W08) and use the OR gate method to provide the /CE signal, you may want to add a pull-down resistor to the CLK line.

This pull-down resistor guarantees compatibility with cartridge readers/writers like the BennVenn joey and sanni's cart reader if you're trying to back up or write new save data. These devices typically don't drive the CLK line when reading/writing SRAM data, which could prevent the FRAM chip from latching properly depending on how you generate the /CE signal.

I've tested this on six of my FRAM modded carts by shunting the CLK line to ground with a 10kOhm resistor and then reading/writing game save data with various devices. still need to test with my n64.


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## MohammedQ8 (Dec 9, 2020)

I wish I bought 5 of them for pokemon games. It plays and saves on Pokemon stadium 1.

Is it discontinued?


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## famiac (Dec 9, 2020)

5 of what? my modded carts are just regular pokemon games. 

I'm pretty sure the drag n derp carts are discontinued. But that's off topic. i would discuss flash cartridges in another thread.


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## MohammedQ8 (Dec 9, 2020)

famiac said:


> 5 of what? my modded carts are just regular pokemon games.
> 
> I'm pretty sure the drag n derp carts are discontinued. But that's off topic. i would discuss flash cartridges in another thread.


I think I would buy gameboy Pokemon games with fram mods if they are stable and well built.

of drag and drop and modded Pokemon games with fram.


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## driverdis (Jun 13, 2021)

Bit of a bump here but has anyone run into the issue of Cypress’s FRAM FM18W08 SOP-28 being too small?

i ordered 10 of them and installed one today but it was a pain since I had to bridge the pad to the pin for every connection since the pads of the chip just touch the pads on the board on both sides.


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## wolffangalchemist (Sep 27, 2021)

I just saved a botched battery upgrade with this for a friend, was pretty grusome so figured i would post it, they got it off a guy who had no idea what they where doing , that poor pokemon silver pcb....  need to order a battery for rtc and possibly fix some traces but saving works again now.


Spoiler: pics


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## Chimicron (Jun 24, 2022)

法条规定


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## Chimicron (Jun 24, 2022)

If you are interested in electronic parts maybe you can find it here


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## Jayro (Jun 24, 2022)

I just prefer to use bootleg carts with batteryless save patches.

You can find a shitload of batteryless patches here:
https://github.com/acocalypso/batteryless-patches/tree/main/patches

And Here:
https://drive.google.com/drive/folders/1NAKO88hWluNngYrQaYPiGqzafPDGmpRE

*"But Jayro, what IS a batteryless patch?"*
A batteryless patch patches the ROM's save routine to dump the SRAM save to the ROM's flash chip, inside part of the ROM itself. It will also load back into SRAM when booted up. This means the game will temporarily freeze the system while it saves your game. But in the end, it saves you from ever needing to replace a battery in your cartridge, and you get peace of mind that your save won't ever just vanish someday from a dying battery. I go batteryless with my reproduction carts any chance I get.

If you buy Pokemon games off AliExpress, you'll notice they are already patched to save without a battery.


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## tech3475 (Jun 24, 2022)

Jayro said:


> I just prefer to use bootleg carts with batteryless save patches.
> 
> You can find a shitload of batteryless patches here:
> https://github.com/acocalypso/batteryless-patches/tree/main/patches
> ...



If you’re intentionally buying bootlegs, wouldn’t it be better to just buy a flashcart?


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## metroid maniac (Jun 24, 2022)

tech3475 said:


> If you’re intentionally buying bootlegs, wouldn’t it be better to just buy a flashcart?


Bootlegs from Aliexpress are extremely cheap (about $5 each) and use much less power than flashcarts*, especially lower end flashcarts like the EZ Flash Jr. They can also be reflashed to play other games, and have the same user experience as legitimate carts for people who just like swapping cartridges. 

*although batteryless bootlegs use a lot of power while saving, which can cause the console to turn off if your battery is low.


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## Jayro (Jun 24, 2022)

metroid maniac said:


> Bootlegs from Aliexpress are extremely cheap (about $5 each) and use much less power than flashcarts*, especially lower end flashcarts like the EZ Flash Jr. They can also be reflashed to play other games, and have the same user experience as legitimate carts for people who just like swapping cartridges.
> 
> *although batteryless bootlegs use a lot of power while saving, which can cause the console to turn off if your battery is low.


All of this is truth. I prefer dedicated carts for most games.
(And with my Etsy shop booming the way it has been lately, apparently other people do too.)

The Chinese Everdrive clones (EDGB v4 on AliExpress, about $25-$29 USD) is lightyears better than the EZ-Flash Jr in terms of power-saving and navigation. It doesn't lag in the menu when searching through games. Games also load faster from my experience of owning both.


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## metroid maniac (Jun 24, 2022)

Jayro said:


> All of this is truth. I prefer dedicated carts for most games.
> (And with my Etsy shop booming the way it has been lately, apparently other people do too.)
> 
> The Chinese Everdrive clones (EDGB v4 on AliExpress, about $25-$29 USD) is lightyears better than the EZ-Flash Jr in terms of power-saving and navigation. It doesn't lag in the menu when searching through games. Games also load faster from my experience of owning both.


I also own one of those EDGB clones. In terms of power saving it might be better than the EZ Jr but it's still worse than a dedicated cart. The kernel also works much better than the EZ Jr in my experience. My EZ Jr crashes whenever it tries to create its own .sav files, for some reason.

I disagree about loading faster, though. The EZ Flash Jr is almost instant. The EDGB clone takes a while to erase and program. But the last-loaded game can be selected instantly, which kinda helps with choice paralysis.


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## Jayro (Jun 24, 2022)

metroid maniac said:


> I disagree about loading faster, though. The EZ Flash Jr is almost instant. The EDGB clone takes a while to erase and program. But the last-loaded game can be selected instantly, which kinda helps with choice paralysis.


Might just be the SD cards I was using, to be fair.


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