Trying to realize BNROM + USB
Posted: Sat May 13, 2017 1:19 am
I'm a layman (read: idiot) when it comes to hardware, but recently I've been entertaining the idea of trying to make a BNROM cartridge that can be flashed (programmed?) via a USB connection. I probably won't succeed in the end, but maybe I can learn something in the process.
Searching around, I'm *guessing* BNROM could use the following parts:
Since Deadly Towers exists, I could probably just use that cartridge's PCB as a starting point. I don't think I'd need an EE degree to figure BNROM out, but correct me if I'm mistaken.
But then we get to the USB part, which seems harder. I want the cartridge to have a USB connector that can retrieve binaries from my computer, without requiring any external devices. I looked at how the Kazzo does it, and it appears to use an ATmega16 for most of the work. It seems like with the V-USB library, an Atmel microcontroller could be wired to the flash memory and that's enough to erase/rewrite it.
I also wonder if it's possible to use a smaller chip than the ATmega16, and if it's possible to combine the USB microcontroller with the CIC microcontroller. A single chip for both sounds ideal, really.
Hopefully someone can straighten things out
Searching around, I'm *guessing* BNROM could use the following parts:
- 804-GLS27SF010-70PHE (1Mbit flash memory)
- AS6C6264-55PCN (64Kbit SRAM)
- 74HC161 (binary counter)
- ATTINY13A-PU-ND (microcontroller for emulating CIC)
Since Deadly Towers exists, I could probably just use that cartridge's PCB as a starting point. I don't think I'd need an EE degree to figure BNROM out, but correct me if I'm mistaken.
But then we get to the USB part, which seems harder. I want the cartridge to have a USB connector that can retrieve binaries from my computer, without requiring any external devices. I looked at how the Kazzo does it, and it appears to use an ATmega16 for most of the work. It seems like with the V-USB library, an Atmel microcontroller could be wired to the flash memory and that's enough to erase/rewrite it.
I also wonder if it's possible to use a smaller chip than the ATmega16, and if it's possible to combine the USB microcontroller with the CIC microcontroller. A single chip for both sounds ideal, really.
Hopefully someone can straighten things out