Hello again, as you may have read yesterday, I'm currently trying to play with some in-system SPI flashing and I need some additional advice.
I just soldered a Pinheader to an Intel D525MW Motherboard (http://www.dont.ru/i/img_1orig/129310882576.jpg - lower right corner) I'm currently not using, but I'm not sure if I should really connect some hardware to it and pull/push on the SPI lines. I suppose it's generally a bad idea to do this, when the Board is currently operating. If it is completely off, I can supply external power and just flash, right? And what about the reset state? I don't have any schematics of my motherboards, so I don't know if there are pull-up or pull-down resistors, I don't know if the chipset really switches its SPI lines into a Z-state, if it is held in reset and so on. I don't want to let the magic smoke escape from my motherboard ;) The only thing I found out is, that the HOLD# ("pauses" the flash chip) and WP# are connected to VCC over a 150 Ohm resistor, each. 150 Ohm is too low for a pull-up, so these two seem to be for limiting the current. Also the pinout is kind of "weird": 1 #CS 2 #CS 3 SI 4 NC 5 SO 6 VCC 7 SCK 8 GND Why is CS# connected to two pins? The resistance between those two pins is 1 Ohm, so they are connected directly. Interestingly the are connected through a 0 Ohm resistor. Any ideas on that? Are there some kind of "best practices" the vendors have when designing those in-system-SPI-flashing-headers? I mean they have to flash these boards in some way by themselves without sending them to heaven, if there is an SPI header. Any advice is greatly appreciated. Thanks, Andreas -- coreboot mailing list: [email protected] http://www.coreboot.org/mailman/listinfo/coreboot
