Hello everybody,
I recently started to discover this great project you have here. I want to play with it a bit and port it to an AMD E-350 Motherboard (Sapphire Pure Fusion Mini E-350 - what a name...) I have at home in my spare time.
Now I don't think that the development work is much fun, when you have to take the SPI chip off the motherboard, program it, put it back into the board, see the code failing and repeat the whole process ;) So, I had the idea of developing a small Board which contains a USB port and an SPI flash. I first thought about emulating the SPI flash completely by an AVR, but I think the clock rates of the SPI bus are too high to do this. My new approach is a SPI flash which resides on the AVR board which can be multiplexed between the AVR to program it and the motherboard. If I want to test a new BIOS, the AVR puts the motherboard into reset, detaches the flash chip with a multiplexer from the motherboard, programs it, switches it back to the motherboard and let off the reset.
Rapid BIOS development :)
As an added bonus, I'm thinking about using a USB 2.0 port of an USB-capable AVR as a USB debug interface (those USB debugging cables are expensive for a poor student ;) ) and add a second USB 1.1 port with a MAX3420 for host-communication, but that's step 2. I know that I won't get the full 480MBit/s with this, but I think I can live with that.
As I am currently looking for suitable parts, I need to know some basic parameters of the SPI communication. Does anybody of you know what the typical clock rates between the chipset and the flash are?
Andy