About GenBIOS Brd4 error?

cdvehicle · ‎2005-07-26

Posted on July 26, 2005 at 22:45

cdvehicle · ‎2005-05-07

Posted on May 08, 2005 at 00:52

the BIOS stoped at ''brd4''( next code is ''Timer0'', BIOS COM post code ), the Hex post code is ''0x24''.but the doc said brd4 is ''as needed at this point'', Hex code 0x24 is ''Init vector tabke'', what's mean? at this point the no signal on ISA bus detected, but PCI ADx toggled. if PCI has any error?

when I remove a PCI device(AD0-AD31 has not disconnect only), It can be run , but when the VGA output is not normal, some time the display color is green only, sometime it output a black screen , the BIOS stop at ''VID1'' or ''splash''

[ This message was edited by: vehicle007 on 08-05-2005 13:42 ]

marios · ‎2005-05-09

Posted on May 09, 2005 at 20:13

You're right on it! The problem happens when the BIOS tries to get information from the PCI devices to build the interrupt table. If the PCI device does not respond to the host properly, the post code 24 is the one that I used to see. Check your clocks/oscillators first.

twitwity · ‎2005-05-10

Posted on May 10, 2005 at 12:24

hi. how is it goin? i can find little time to do any other thing than doing my work these days.

if your board is not very different to original demo board, the BIOS should work relatively smooth.

and PCI interrupt table is written automatically if you route IRQ line on board normally. so. the BIOS post error may caused by graphics BIOS. graphic is initialized before board bios initializes board. try check VGA BIOS by inserting PCI VGA card and check in BIOS menu, VGA option whether internal VGA is on or PCI VGA is on.

and maybe this is done with your board this time right? the actual data is lacking. which is usual with this kind of debugging. but try to be more specfic.!

marios · ‎2005-05-15

Posted on May 15, 2005 at 19:02

what memory chips are you using? Are you using a DIMM socket, or do you solder memory chips directy on-board?

cdvehicle · ‎2005-06-10

Posted on June 11, 2005 at 04:41

I used solder memory on my board, I think the STPC's PCI Bus should be damage. It is very diffcult to repair it I think. I wiil be crazy. luckly , I make a new board, It can be running, but some time it tell me the same question, so perhaps the PCI has some error I can not found, the first borad may be right!

[ This message was edited by: vehicle007 on 11-06-2005 08:19 ]

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Attachments :

PCI.jpg : https://st--c.eu10.content.force.com/sfc/dist/version/download/?oid=00Db0000000YtG6&ids=0680X000006Hts4&d=%2Fa%2F0X0000000aYA%2FYAmO0spQvlIyYOjn4yuQ3tZX0hAELAs6Catj5YBAmto&asPdf=false

cdvehicle · ‎2005-06-12

Posted on June 13, 2005 at 03:40

Do you have any tools to modify GenBIOS's default data, then I can

remove the battary.

marios · ‎2005-07-26

Posted on July 26, 2005 at 22:45

I hope your design has advanced since the last post.

So you said that the CPU runs when you have no PCI device attached. Well, all you need to find now is what PCI lines are conflicting with your PCI chip. (what is it?) I even had an unpowered PCI device on a board, and it did not prevent the rest of the board to boot properly.

If you get the Post code 24, the CPU sees something and tries to access it, but it can't and possibly loops on the error.

If you have any postcode, it means that your ISA bus is mostly working, as the BIOS data goes through it.