PCChips M810LR-H

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JEWilson
Chip off the ol' block
Posts: 109
Joined: Wed Oct 11, 2006 12:51 am

Small problem with this mobo

At POST, the mobo halts with a CMOS Memory wrong error.
BIOS version installed Release 04/15/2002 S
The mobo reports soft errors as with;
Press F1 To Run Setup
Press F2 To Load Default Values And Continue

However keyboard is dead.
Suspected a BIOS problem.

I have an update BIOS Release 08/08/2003 S
Flashed this image with my Willem
Installed in mobo
At POST have same problem as with orig. BIOS

Noticed the bios image to be 256k compressed
Indicates a 1Mb BIOS
THe DIP32 IC is a SyncMOS U29C51002T-90PC
This is a 2Mb 5V part

To confirm, would this be the problem and source of
CMOS memory wrong message
My POST diag. card reports 8582

LH Code - real time value, RH Code - previous value
AMI Code 82 - KeyB controller interface test over.
About to write command byte and Init circular buffer.
Chk. for printer ports and put addresses in global data area.

Must have processed 83 & 84 implictly
-------------------------------------
AMI Code 83 - Command byte written, global data Init done.
About to check for lock-key.
Chk. for RS-232 ports and put addresses in global data area.

AMI Code 84 - Lock-key checking over.
About to check for memory size mismatch with CMOS.
Co-processor detection over.
80287 check/test ok.

AMI Code 85 - Memory size chk. done
About to display soft error and chk. for password or bypass setup.
About to display soft error message.
If no video replace video card.

Obviously, POST halts at AMI Code 85

Solution?
Resolve with using a 1Mb part?

Please advise. Thanks.
cp
BIOS Guru
Posts: 1914
Joined: Mon Oct 21, 2002 9:07 pm
Location: Germany

all M810 bios files are 256kB (or 2MBit). to overcome the failure message you have to replace the battery, set the clear cmos jumper to normal, enter the bios and exit saving the settings. that's it. if the keyboard isn't working check for bulged caps especially near the ps/2 ports. check for +5V power on the ps/2 kb connector and check the fuse, too. and make sure you didn't plug the keyboard into the mouse port.
If you email me include [WIMSBIOS] in the subject.
JEWilson
Chip off the ol' block
Posts: 109
Joined: Wed Oct 11, 2006 12:51 am

Thx for that
Did change batt. as a matter of course.
Did suspect the PS/2 port was at fault.
There are no electrolyitcs at fault per se.
All of the major lytics above 470uF test ok for ESR failures etc.

As it is a PC Chips mobo, there is no fuse as such,
rather it is just a solder link called F1. This is ok.
However, there are further, what appear to be SMT
caps in series with the connector, or at least they
look like SMT caps. The decal for these devices
designate these to be FB1, FB2, FB3, FB4 and FB5
and they are in series with the PS/2 connector housing.
These act, I suspect as fuse links and are actually
inductors - they read down to 0.2R with a MMeter.
I compared the phy. description with others on the pcb.

They all test ok (get continuity) with the exception of
the last one, FB5 - this is open.
Being as they test s/c across the device but with the above
exception, FB5 further looks discoloured as if from
heat damage.

I have a copy of the Amp PS/2 Housing part.
Whereas it shows a 6 pin mini-din elevation, the
pcb side of the connector shows an 8 pin layout .

I am unsure about the correct pinout here.
Perhaps someone couuld advise such that I can confirm
whether the suspect device is on the +5.0 v line of
the keyboard or if it is something else.

Thanks.
JEWilson
Chip off the ol' block
Posts: 109
Joined: Wed Oct 11, 2006 12:51 am

Problem resolved. Was indeed FB5.
Replaced with a recovered component from another mobo

Thanks for the help
RTHawk
New visitors - please read the rules.
Posts: 2
Joined: Tue Sep 08, 2009 7:23 am

I am experiencing the identical problem with this exact mobo - right down to the same codes on my pc analyzer card. I just want to be clear that this is a mobo failure that requires soldering and removing something on the mobo then replacing that 'something' - the FB5 component? I've never done this...is the FB5 something easily found a another mobo?
JEWilson
Chip off the ol' block
Posts: 109
Joined: Wed Oct 11, 2006 12:51 am

If you have a programmer like a Willem
You could reflash the bios IC out of cct.
This would eliminate the BIOS image as being at fault.

The inductor FB5 is of a standard size.
You can usually use this as a good indicator when
selecting a component from another mobo.
So... same size, likel to be same rating.

Care should be exercised as you want to use an
SMT inductor and not an SMT capacitor or SMT resistor.

HTH
RTHawk
New visitors - please read the rules.
Posts: 2
Joined: Tue Sep 08, 2009 7:23 am

Thank you for you quick reply.

I'm a hobbyist so I'm ignorant of your abbreviations:
bios IC out of cct = ?

I found a good web site with mobo component basics to show me what all the parts look like at pcguide dot com so I was able to see what a SMT inductor looks like, however I'm not sure which one is the FB5 on my mobo. I happen to have another board - the M810LV that I could take it from.

Any more detailed how to explanations would be appreciated. Thank you.
cp
BIOS Guru
Posts: 1914
Joined: Mon Oct 21, 2002 9:07 pm
Location: Germany

if it's really the inductor that's blown, you can simply short it. it's just there to reduce EMI.
If you email me include [WIMSBIOS] in the subject.
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