The BIOS settings are stored in the CMOS ram which is traditionally in the RTC chip. On later motherboards it was integrated into the chipset along with the RTC.

A quick test of the cmos/rtc health for integrated chipset solutions is to measure the current draw from the battery with the machine off. Your mobo has an AT style power connector, which does not have standby power like ATX. When the PC is off it should be using the battery.

Excessive current draw from the battery, or zero current draw (in nano amps) is a sign the chipset has a problem.

Another thing to check is that battery voltage is actually making it to the Vbatt pin on the chipset. Look up datasheets to find this.

Hmmm make sure J1 ad J4 are jumpered AND "hardware reset" jumper by the cpu socket is not jumpered....(just a thought)
and some boards get a hard reset when saving/exiting bios. Can you save BIOS settings w/o exiting BIOS ? some you can, some you can't. If you can then do a Ctrl-Alt-Del for soft reset and go back in bios.

After re-reading am thinking your current eeprom chip may be bad if you cannot proper flash it. The original flash for a PA-2002 is Award 5.2c
ftp://ftp.algo-hk.cz/MIRRORS/ftp.fica.com/BIO … boards/pa-2002/

Horun wrote on 2024-03-01, 02:07:

After re-reading am thinking your current eeprom chip may be bad if you cannot proper flash it. The original flash for a PA-2002 is Award 5.2c
ftp://ftp.algo-hk.cz/MIRRORS/ftp.fica.com/BIO … boards/pa-2002/

He's losing settings and getting CMOS checksum errors. None of that is stored in the EEPROM.

kingcake wrote on 2024-03-01, 03:25:

Horun wrote on 2024-03-01, 02:07:

After re-reading am thinking your current eeprom chip may be bad if you cannot proper flash it. The original flash for a PA-2002 is Award 5.2c
ftp://ftp.algo-hk.cz/MIRRORS/ftp.fica.com/BIO … boards/pa-2002/

He's losing settings and getting CMOS checksum errors. None of that is stored in the EEPROM.

Yes he has a cmos issue but this:

net5rac wrote on 2024-02-28, 22:55:

I have tried different BIOS versions but always the flashing/comparison shows areas with errors.
Only when I flash the original/backup BIOS it seems the flashing worked. But I suspect flashing does not work in any case, even the backup BIOS did not flash.

tells me he may also have a eeprom issue....

OP, what is the history of this motherboard? Looking at the jumper manual from https://theretroweb.com/motherboards/s/fic-pa-2002#docs, it appears there is a jumper setting to choose between two different EEPROMs (J2) - this is almost certainly a voltage setting. If it isn't set correctly, it could mean that the EEPROM isn't getting the correct voltage; this might be why you cannot flash the BIOS. If the EEPROMs model number/brand is covered up, I would peel back the sticker to verify that J2 is set correctly.

Hi! Thanks a lot for the replies.
I have been a bit busy last weeks, but here are my answers:

@kingcake - I have put a piece of paper between the CMOS battery and the clip and have measured current between clip and battery. Hope this is the right way to measure. Nothing else was connected to the motherboard. The current was about 3mA. I don't know where to find the Vbatt pin to measure the voltage.

@Horun - I have triple checked all the jumper settings. J1/J4 are closed and the reset pins next to the CPU are not closed. Only the beeper is connected to the pins next to the CPU.
In the BIOS settings I can only do Save&Exit which is followed by a soft reset (I think). If I directly go to the BIOS again after saving, the values are not saved, only the time continues running.
When I Save&Exit and wait, the boot process always stops with CMOS checksum error and CMOS Battery failure.

@Repo Man11 - I was using UNIFLASH to flash the BIOS. UNIFLASH was showing SST 29EE010 BIOS chip which fits to the jumper setting on the board (pin 1+2 closed).

I have tried different CMOS batteries w/o success just to rule out the battery is the issue. Still the behaviour was as if there is no battery installed.
As mentioned above the fact that no CMOS settings are saved and that I cannot flash the BIOS feels as if there is a write protection to the BIOS/CMOS, viz. voltages are not where they should be.

The board has an external battery header, that I could try out. Can I use AAA batteries to connect them to the header? How many will I need? I read somewhere that there are diodes that let voltage drop. Thus I may need higher voltage than 3V (more than 2 batteries).

Thanks for your help!

The fact that the clock keeps on running indicates the 3V voltage reaches the VIA southbridge (VT82C576M). It still w0n´t save anything to the integrated CMOS memory. I would think of either some issue with the ISA bus or a defective southbridge.
Do different kinds of ISA cards work correctly - like I/O cards / Floppy dtive or video cards?

Since I cannot find a datasheef for this chipset, I´m not sure if the nearby VT72C577M is a buffer circuit between the ISA-slots / BIOS chip / super-I/O and the southbridge. The CMOS memory is integrated in the southbridge without a doubt.

A quick test of the cmos/rtc health for integrated chipset solutions is to measure the current draw from the battery with the machine off. Your mobo has an AT style power connector, which does not have standby power like ATX. When the PC is off it should be using the battery.

Excessive current draw from the battery, or zero current draw (in nano amps) is a sign the chipset has a problem.

Another thing to check is that battery voltage is actually making it to the Vbatt pin on the chipset. Look up datasheets to find this.

I have put a piece of paper between the CMOS battery and the clip and have measured current between clip and battery. Hope this is the right way to measure. Nothing else was connected to the motherboard. The current was about 3mA. I don't know where to find the Vbatt pin to measure the voltage.

Horun wrote on 2024-02-29, 03:17:

Hmmm make sure J1 ad J4 are jumpered AND "hardware reset" jumper by the cpu socket is not jumpered....(just a thought)
and some boards get a hard reset when saving/exiting bios. Can you save BIOS settings w/o exiting BIOS ? some you can, some you can't. If you can then do a Ctrl-Alt-Del for soft reset and go back in bios.

I have triple checked all the jumper settings. J1/J4 are closed and the reset pins next to the CPU are not closed. Only the beeper is connected to the pins next to the CPU.
In the BIOS settings I can only do Save&Exit which is followed by a soft reset (I think). If I directly go to the BIOS again after saving, the values are not saved, only the time continues running.
When I Save&Exit and wait, the boot process always stops with CMOS checksum error and CMOS Battery failure.

Repo Man11 wrote on 2024-03-01, 16:41:

OP, what is the history of this motherboard? Looking at the jumper manual from https://theretroweb.com/motherboards/s/fic-pa-2002#docs, it appears there is a jumper setting to choose between two different EEPROMs (J2) - this is almost certainly a voltage setting. If it isn't set correctly, it could mean that the EEPROM isn't getting the correct voltage; this might be why you cannot flash the BIOS. If the EEPROMs model number/brand is covered up, I would peel back the sticker to verify that J2 is set correctly.

I was using UNIFLASH to flash the BIOS. UNIFLASH was showing SST 29EE010 BIOS chip which fits to the jumper setting on the board (pin 1+2 closed).