- Jul 21, 2015
- Reaction score
- NH, USA
Indeed, it took me approx 400 hours to reverse engineer the logic and re-create the security algorithm it implements.
The FPGA sits across the entire bus, the cartridges function as an extended G1 bus device. Flash and PIC are both controlled through it's logic.Does it sit on the bus between ROMs and motherboard, or is it separate? Do you have any notes or pinouts you don't mind to share?
I reverse engineered and have made a reproduction cartridge based on the "M4 cartridge" (Part number 171-8346C). This is backwards compatible with all other cartridge types/games. But given the parts cost it doesn't make economic sense to produce a single game cartridge.Do you have any notes or pinouts you don't mind to share?
Edit: Ok, I'm caught up on the thread. And I had a peek at the mame driver for Naomi and the decryption.
So, do I understand it correctly and the repro PCB would just be a 171-7919A without the protection gubbins? Or is anything of that still used by the game, like some DMA hardware?
Would it be worth integrating the 27c322 with the other ROMs into one linear map, so that there is room for the "leftover" bits?
(Slightly off topic: Is it worth buying a Naomi 2 or Naomi 1?)
512mbyte PC-133 SDRAMDepends. I've substituted RAM with flash before and it worked just fine. I guess it depends of the brand, size, etc.
I skipped on the encryption as it is not required. The g1bus protocol is not specifically protected, but it uses additional commands that are not documented along with a challenge/response algorithm that authenticates the cart (it's a fun one, starts with a random seed and continues while running)I don't plan to implement the encryption, it would need to be "net-bootable" versions in the first place.
Is the minimum "flash + G1 device", or is that protocol protected as well before the bios attempts to use it?
probably worth to mention - there is 2 kinds of cartridgesThe FPGA sits across the entire bus, the cartridges function as an extended G1 bus device.
please check if it maybe undumped revision, older DOC versions which uses 171-7919A is not common and I suppose we might miss some of these.I've got a Derby Owner's Club on the way, which is 171-7919A
I looked up the board from the dumped ROM list, so until I open it I don't know what'll be in it. If it is anything rare I'm going to get it dumped.please check if it maybe undumped revision, older DOC versions which uses 171-7919A is not common and I suppose we might miss some of these.while most common at ebay DOC World Edition uses 171-8132B rom board type.
Well, I couldn't find a Ridge Racer Full Scale.Derby Owner's Club is pretty big for the man's cave...
100% conversion. Was never released as a cart.I'm pretty sure this has been discussed before. I have seen a few Ikaruga cartridges on Ebay and can't determine if they are legit or converted. Ikaruga only released on GD-ROM afaik.