Josh wrote: > > Good, the chip is supported by flashrom. > > I'm having troubling finding a place to buy a W39V040B chip in the > US. Looks like avnet.com is a good place to buy an alternative > chip, but I can't to find any information on how to pick a chip > that is compatible. What criteria do I need to look at when > picking out a different chip.
There are a few parameters that have to match; * Package, usually one of: * DIP32 (for parallel) * PLCC32 (for parallel and LPC and FWH) * TSOP32 14mm (for parallel and LPC) * TSOP32 20mm (for parallel and LPC) * SO8 200mil (for SPI) * SO8 150mil (for SPI) * DIP8 (for SPI) * Protocol, one of: * ISA (parallel) * LPC (serial 4-bit) * FWH (serial 4-bit) * SPI (serial 1-bit) * Signalling * 5V (for parallel) * 3.3V (for LPC and FWH and SPI) W39V040B is LPC, and available in PLCC32 and TSOP32. PLCC is much more common. Any other LPC PLCC flash chip will work. > While I'm at it, I'd like to go with a bigger chip unless there is > a reason not to. As others mentioned this depends on how the (in this case LPC) bus master can be configured. The southbridge needs to decode (bus terminology for route or connect) the entire memory area that would be occupied by a larger flash chip onto the LPC bus where the chip is connected. >From the SB600 RRG it seems the full 4GB address range can be decoded onto LPC in steps of 64k, meaning that you will be able to use as large a flash chip as you can find. I suggest trying to find one of two SST flash chips; SST49LF016C-33-4C-NHE or SST49LF160C-33-4C-NHE (66 instead of 33 is fine, but N in NHE means PLCC so is important) If I remember correctly, one is LPC only and the other is combined FWH/LPC, but I would like someone else to confirm this. The data sheets on these two parts are unfortunately not at all helpful. These parts are both 16Mbit = 2Mbyte so you'll have some room for using a Linux kernel as payload. //Peter -- coreboot mailing list: [email protected] http://www.coreboot.org/mailman/listinfo/coreboot
