[coreboot] Free chips, not required by me, and a question

Carl-Daniel Hailfinger c-d.hailfinger.devel.2006 at gmx.net
Mon Dec 1 23:57:00 CET 2008

On 01.12.2008 11:40, Chris Lingard wrote:
> Carl-Daniel Hailfinger wrote:
>> On 29.11.2008 10:57, Chris Lingard wrote:
>>> Now I need help, my machine has Pm49FL004 chips as standard, I have
>>> some Pm49FL008 too.
>>> I want a 32 M Bit flash chip, if there is such a thing for this type
>> Can you tell us more about your mainboard chipset? The Pm49FL004 can do
>> LPC and FWH, but a board only needs one of them.
>> I thought I had seen some data sheets for 32 Mbit chips, but it seems
>> they all were SPI and not FWH/LPC.
> Thanks for all the information.  I have done some reading and got the
> data sheets.  My chips are PLCC, (nearly square with pins on all four
> sides).

Ah, that's an old trap. Your chips have a PLCC32 housing, but the
housing is unrelated to the protocol used by the chips.
The protocol for recent chips can be LPC, FWH and SPI. To make matters
more complicated, FWH is a special case variant of LPC with one bit set
differently. That means some data sheets mention the chips speak LPC
although they will not respond to regular LPC read/write cycles.

I've tried to create a marketing language -> chip type mapping below:
- FWH -> FWH
- Firmware Hub -> FWH
- LPC Firmware -> FWH
- Firmware Memory -> FWH
- Low Pin Count (if Firmware/FWH is not mentioned) -> LPC
- LPC (if Firmware is not mentioned) -> LPC

SST data sheets have the following conventions:
"LPC Memory Read" -> LPC
"Firmware Memory Read" -> FWH
If both are mentioned, the chip supports both.

> So am I stuck?  They do not make large capacity {SST,Pm}49LF0??) PLCC
> chips, or is it just an old chip?



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