Multi Region Super Game Boy
A PAL Super Nintendo game can only be played on an unmodified PAL Super Nintendo console. This is due to the CIC lockout chips, one in the console and one in the cartridge. I have written previously about replacing the chip in the console to allow it to play any region game, but what about the other way round?
If you have the desire to make a Super Nintendo game work on any region console, you are in luck, not only did ikari make a replacement CIC ‘lock’ chip for the console, he made a replacement CIC ‘key’ for cartridges too!
It works by booting the cartridge as one region, if it doesn’t work, when you hit reset, it tries as the other. If it is successful, it remembers its state for the next time it is powered on.
While we are talking about CIC chips, here are a few photos of some different SNES game PCB’s, each with a different lock out chip.
First is Street Fighter II Turbo. It has a D413A CIC, through hole DIP16 chip. Next is Doom, it has a surface mount 18 pin chip, which is the same as the lockout chip in the PAL Super Nintendo console, just connected up differently. I can only assume they changed the lock out chip in later games as they were using all surface mount components (apart from the XTAL). The last one is PGA Tour 96. It doesn’t have a CIC chip per say, but the SA1 chip handles all the region checking duties, in a more complex way than the basic CIC.
The Super Game Boy uses one of the F413A surface mount chips, and in order to add the SuperCIC, I had to remove it, which I did with my trusty soldering iron and solder sucker.
PAL Super Game Boy PCB (orange/red/black wires on the left go to an EXT port I had previously added)
Close up of the F413A CIC chip
Close up of the PCB with the F413A CIC chip removed
Close up of the removed F413A CIC chip
Next, I flashed the SuperCIC key code to a PIC12f629 and soldered it to the Super Game Boy as per the instructions in the source file. It mentions that an LED can be added to pin 3 to show what state the chip is in, LED lit means everything is OK, LED off means there is an error. I decided to add a tri-colour LED, with one leg wired to 5v (via a 220R resistor), the middle leg to ground, and the other to the output pin on the SuperCIC (also via a 220R resistor). By wiring it like this, if the SuperCIC can’t boot the cartridge when you turn on the console, the LED lights up red. When you hit reset, the SuperCIC then boots the cartridge, and outputs a signal on pin 3 making the LED light up orange. A nice addition being as the original Super Game Boy doesn’t have a power LED (or an EXT link port). The Super Game Boy 2 has both of these features, it was only released in Japan though.
PAL Super Game Boy PCB fitted with SuperCIC (key) chip
Here is a video demo of the muli region Super Game Boy working, my very first video!
If you have an urge to read more about the CIC lock out chip and find out how it works, have a read of this at hackimii.com or this thread over at nesdev.parodius.com.