Hi guys (and girls). Good morning (at least here GMT+1) ;).
Well this morning I did with the help of the multimeter a continuity test between the soldered bios and the pins that seems to be a second bios socket, you know.
The majority of the pins are directly connected, but there are a few that aren't. Here are what pins are NOT connected to each other on the two sockets:
1,9,10,11,12,19,20,21,22,24,26,27
Maybe are unused, I don't know, and worst, I dont understand on the datasheet of the chip what means the three names that are given to the pins, each for these columns: A/A Mux, LPC, FWH. If someone can clarify it ...
Another thing is something that a friend of mine says yesterday: why instead of removing the chip, take and desolder only the vcc pin, put a micro-switch on it, solder another chip on top of the existing and do the same with its vcc pin, so with two micro-switches you can select wich bios chip use. What do you think about this solution?. If the other socked is directly connected, I don't understand the three modes of operation of the chip as I say previously, it will be a good thing installing the switches to both sockets and leave the original for backup and life-guard, and use the second for testing,working,etc.
Thats all folks, for the moment ;).
Have a nice day. Jose.
* Beth beth.null@gmail.com [070328 11:22]:
Maybe are unused, I don't know, and worst, I dont understand on the datasheet of the chip what means the three names that are given to the pins, each for these columns: A/A Mux, LPC, FWH. If someone can clarify it ...
The PMC chip can be used in two operation modes, LPC and Firmware Hub. No idea what A/A Mux is. Depending on the operation mode, the pins have different meanings.
Another thing is something that a friend of mine says yesterday: why instead of removing the chip, take and desolder only the vcc pin, put a micro-switch on it, solder another chip on top of the existing and do the same with its vcc pin, so with two micro-switches you can select wich bios chip use. What do you think about this solution?.
You also need to do this for CE and CS.
No idea how hard or easy it is to desolder single pins instead of the complete chip. It is a good idea though!
On Wed, Mar 28, 2007 at 04:52:49PM +0200, Stefan Reinauer wrote:
- Beth beth.null@gmail.com [070328 11:22]:
Another thing is something that a friend of mine says yesterday: why instead of removing the chip, take and desolder only the vcc pin, put a micro-switch on it, solder another chip on top of the existing and do the same with its vcc pin, so with two micro-switches you can select wich bios chip use. What do you think about this solution?.
You also need to do this for CE and CS.
Actually not, there are no CE or CS signals here.
But don't use Vcc, use INIT# instead.
We just need to learn how it looks during boot and how it is connected on the two chips, then the U10 pads can be used to fit a socket and T1/T2 pads used for the switching circuitry.
No idea how hard or easy it is to desolder single pins instead of the complete chip. It is a good idea though!
Too hard, better just use the ready made PLCC pads for a socket. :)
//Peter
Stefan Reinauer wrote:
Another thing is something that a friend of mine says yesterday: why instead of removing the chip, take and desolder only the vcc pin, put a micro-switch on it, solder another chip on top of the existing and do the same with its vcc pin, so with two micro-switches you can select wich bios chip use. What do you think about this solution?.
Having a chip on your LPC bus with data and address lines connected but with no Vcc will mostly likely screw you. Operation of the chip will be undefined.
You also need to do this for CE and CS.
No idea how hard or easy it is to desolder single pins instead of the complete chip. It is a good idea though!
On PLCC it will be pretty hard since they are not really pins that you can just lift up off the pad.
-
Beth -
Peter Stuge -
Richard Smith -
Stefan Reinauer