SUPER FX2 super multi eprom-overclock- multi game save battery backup cart

What I would like to show is something I'm sure will be very interesting to people who only want the absolute best in both game play, game saves along with the experimentation of SUPER FX2 clock speeds, this is still in its very early stages but you will be able to see what I have done thus far. I have excellent soldering skills, so none of this was any trouble for me, I work on circuits 10X smaller in my self-owned business here in Australia and this was basically child’s play. I will try to showcase this as an easy to follow guide, I’m very happy to answer any questions also. Did I mention that I live and breathe RETRO, lol, let’s begin?



















A picture tells 1000 words.

This is just the EPROM mounting stage of this mod, in the coming weeks I will post more stages of progress.
Lots of people have inspired this project, so to them I say thank you.
This POST will be updated continually so as to provide a one click and stop area for viewing, basically you won't have to dig through a heap of pages to follow this guide, and all related information to my mod will stay in this first POST area, cheers.

Haha a zif. I just used a precision socket.

Tiido taught me a much quicker and easier way to lift the maskrom and anything surface mount. Just bridge all the pins on the one side with solder and keep the entire side hot with the iron and lift the whole side at once. Works great and it's very easy cleaning up the solder once the chip is lifted.

You also forgot to post the eprom wiring chart:



Which I stole from here:

http://www.omgrofl.com/?p=23

Winter gold is the best possible superfx donor as it has a gsu2, the most ram ever used in a superfx cart, and a battery saving circuit. However wiring up an eprom socket in winter gold is a bit strange because the savedata will be lost when you change the game. That's why I hard wired my winter gold cart as a stunt race fx cart.

As for the inspiration this "brit with a soldering iron" who actually insulted me on assemblergames was helpful for making a nice chart for the eprom wiring as well as mentioning which eprom works.

A big thankyou to robivy64 for giving me the idea of using a 4 pin crystal oscillator as the old 2 pin crystal overclock mod didn't work at all. I was the first person to try using a 4 pin oscillator on the gsu 1 and gsu 2.

I think I was also the first person making repros using the gsu 2, and I'm certainly the first person to properly overclock both the gsu 1 and 2.

The only downside I can see of what mr. nu did is he covered the lockout chip in glue. So now his cart is pal only unless he feels like removing all that glue and swapping the lockout chip.

Anyway I'm always looking out for someone who can do the eprom wiring for a fairly cheap price. Right now I'm charging 120$ to do the eprom wiring / burning and overclocking because truthfully...I hate wiring these carts. If you can build these carts for cheaper that would bring down the cost of making the overclocked superfx carts and you could just pay me a percentage of the commissions. Overclocked superfx games are my second best selling product but I really hate doing the eprom wiring haha.

*edit*

I gotta start sticking a business card into all of my pictures!

I think you will find that a precision socket will damage an EPROM due to the fact that this cart will be getting a lot of EPROM swaps, precision sockets in that sense would be a very dangerous to the pins of the EPROMs, ZIF sockets are used in just about every pic/EPROM burner on the market for that reason, however I do intend on using 32 pin sockets for a type of caddy to protect the EPROM, I will post pictures of them when they arrive, any day now, as for the EPROM to mask rom guide, I never forgot, I was getting to it as the post was still young and I wanted to do something different, lol, I have a much simpler one for people to follow, no pictures, just pin to pad, so without further delay,,,,,,,,

M27C801 Pin to Pad connection changes:

Pin 1 to Pad 30
Pin 2 to Pad 24
Pin 31 to Pad 2
Pin 30 to Pad 1
Pin 24 to Pad 31

All other Pins to their corresponding Pads.

The lock out chip is not a problem for me as I have a Pic controlled switch in my SNES, also the game is Pal and I live in Pal land, lol, but really this is for my personal use and I have no issues with the lock out chip anyways. As for save data everything is so easy, I will have two options for this in future posts, also any doom cart can have a very simple mod done to it to manage save game data, much simpler then the brit's expensive and costly mod, but you will all have to wait and see; this cart can do it all.

From my personal experience the zif sockets have a harder time making good connections than the precision sockets haha. I mean I don't stick the eprom directly into the precision socket it goes eprom into its own precision socket into the other precision socket and that's as good of a connection as you can get.

I know that the lockout isn't a problem for you but when making a cart for someone else usually the ntsc lockout chip is more popular. As for your doom circuit you'll have to wait and see just how long the battery lasts. We tried wiring up a doom cart with the circuit posted in the brits blog and it drained a new battery after about 2 weeks. I didn't do the wiring but clearly something wasn't working right.

I only use GOLD ZIF sockets made by the 3M corp, they have never let me down so far, my save mod is nothing like the brit's, I can't see what is going wrong with the 2 week lifespan thing, my mod is that simple it will make people want to slap themselves, anyways the multi sram with multi bat back up will be seen in the next couple of weeks.

sounds good.

First post updated with more pictures and more easy to follow information.

Awesome thanks for the update. I'm really interested in your battery circuit too so I can't wait to see that.

Drakon wrote:

Awesome thanks for the update. I'm really interested in your battery circuit too so I can't wait to see that.

Yes... I'm just waiting for my experiment to conclude, and for more parts to arrive, this thing is a crazy setup, my vision in mind is that it will be a custom mount with a switch that will host all SRAM chips for each super FX rom that saves (this needs to be confirmed by way of experiment conclusion) and one SRAM will be for graphics frame buffer only use with regard to the games that don't, I can't wait to showcase this, this is 100% my idea and is unique, I will also showcase my second option, it can also just be a swap out SRAM for each save game super FX rom, or something else, I can't confirm the last option yet because I have not done the experiment, I CAN'T WAIT!!!

I think I have isolated a pin on the SRAM that could be used in conjunction with a switch to activate or deactivate different SRAM while still keeping power live to the said SRAM, this would enable one SRAM chip to be used with an installed EPROM, then deactivated and another SRAM activated for another EPROM so that the first SRAM is left unchanged, I’m busy jumping wires, this is very small work and I should have everything wired up in 2 more days, if I get enough free time. I would like to ask someone out there to email me some high res pictures of a doom cart, both sides please and would like to ask for volunteer to take on a doom cart experiment. Thanks. I will just buy a doom cart if no one comes through, I have but already invested a stupid amount in this project, lol, but it is great fun, and cheaper than the pub.
Email pictures and or volunteer status to swhhouston@gmail.com

I have just purchased a SNES doom cart very cheap, I would like to cancel the request for someone to do an experiment for me on the same said cart. Thanks anyway.

NERVES of STEEL; 1/2 done having a coffee or a cup of tea? Will do the tea, need a steady hand, lol.



This is a 512Kb SRAM from a SNES cart, I intend to mount it and along with another, switch one pin to isolate each SRAM and attempt my multi save experiment, in theory it works, but so does communism. I will be back soon with the results and maybe a video as well.

I would take the coffee. Need the extra focus. Then again I would glue the sram against a piece of breadboard and feed pins through breadboard holes and solder them into the holes. That way you could bend the pins to lines up with the sram pins and both the sram and metal pins would be held in place so soldering them together would be nice and easy.

The pins are very tight and very short, in the end; if the experiment is successful, the entire SRAM bank will be mounted on a custom PCB with dip switch selector all wired into one battery with a high MAH ratting, except for one SRAM; witch will be for the games that don't need to save.