Troubleshooting computers
 

Hello,
I have a good background in electronics and troubleshooting, but need
some help in how to troubleshoot microprocessor circuits/ computers. Are
there any techniques that help to determine if a processor circuit is
working properly other than just running it, and if there is no
troubleshooting software for it? Is it just a matter of checking to see if
data is moving? How can you tell the data is correct? Any help in
troubleshooting these types of circuits is appreciated. Thanks.
B

Troubleshooting computers
 

"Brian O" wrote in message
...
Hello,
I have a good background in electronics and troubleshooting, but need
some help in how to troubleshoot microprocessor circuits/ computers. Are
there any techniques that help to determine if a processor circuit is
working properly other than just running it, and if there is no
troubleshooting software for it? Is it just a matter of checking to see
if
data is moving? How can you tell the data is correct? Any help in
troubleshooting these types of circuits is appreciated. Thanks.
B

Mostly it is done by board/module swapping.

Steps that can be used (but not often used as a scope is often required):

1/ Check all supply voltages
2/ Verify the clock signal
3/ Verify all inputs
4/ Verify activity on the busses

Troubleshooting computers
 

"Brian O" wrote in message
...

Hello,
I have a good background in electronics and troubleshooting, but need
some help in how to troubleshoot microprocessor circuits/ computers. Are
there any techniques that help to determine if a processor circuit is
working properly other than just running it, and if there is no
troubleshooting software for it? Is it just a matter of checking to see
if
data is moving? How can you tell the data is correct? Any help in
troubleshooting these types of circuits is appreciated. Thanks.

You pretty much can't. Most computer shops don't even own a DMM.

Troubleshooting computers
 

I have a related question: how would you troubleshoot a motherboard which
resets CMOS to default every time a/c power is shut off, even with a fresh
battery?

I have another identical board (ECS N2U400-A ver1.0) which functions just
fine, and thought about
doing an A-B type comparison with a meter, but I'm not sure what to look
for.


"Homer J Simpson" wrote in message
news:Q8lIh.34647$Du6.12346@edtnps82...

"Brian O" wrote in message
...

Hello,
I have a good background in electronics and troubleshooting, but need
some help in how to troubleshoot microprocessor circuits/ computers. Are
there any techniques that help to determine if a processor circuit is
working properly other than just running it, and if there is no
troubleshooting software for it? Is it just a matter of checking to see
if
data is moving? How can you tell the data is correct? Any help in
troubleshooting these types of circuits is appreciated. Thanks.

You pretty much can't. Most computer shops don't even own a DMM.

Troubleshooting computers
 

"KenB123" wrote in message
...

I have a related question: how would you troubleshoot a motherboard which
resets CMOS to default every time a/c power is shut off, even with a fresh
battery?

Bad CMOS ram or bad battery connection. How much current does it draw from
the battery while off?

Troubleshooting computers
 

I haven't yet got to the point of measuring current drain, but the battery
seems to be holding at 3v.

However when this problem first cropped up, the original battery was weak.
So maybe there is a drain somewhere.

"Homer J Simpson" wrote in message
news:HRIIh.62326$Du6.60575@edtnps82...

"KenB123" wrote in message
...

I have a related question: how would you troubleshoot a motherboard which
resets CMOS to default every time a/c power is shut off, even with a
fresh
battery?

Bad CMOS ram or bad battery connection. How much current does it draw from
the battery while off?

Troubleshooting computers
 

"KenB123" wrote in message
...

I haven't yet got to the point of measuring current drain, but the battery
seems to be holding at 3v.

Voltage is only useful diagnostically on the CMOS chip. Current is a quick
and dirty check.

Troubleshooting computers
 

Homer J Simpson wrote:

"KenB123" wrote in message
...


I have a related question: how would you troubleshoot a motherboard which
resets CMOS to default every time a/c power is shut off, even with a fresh
battery?


Bad CMOS ram or bad battery connection. How much current does it draw from
the battery while off?



If you can measure that, you've got a d*mned good meter.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Troubleshooting computers
 

Homer J Simpson wrote:

"KenB123" wrote in message
...


I haven't yet got to the point of measuring current drain, but the battery
seems to be holding at 3v.


Voltage is only useful diagnostically on the CMOS chip. Current is a quick
and dirty check.



Methinks you know not of what you speak.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

Troubleshooting computers
 

"Charles Schuler" wrote in message
. ..

"Brian O" wrote in message
...
Hello,
I have a good background in electronics and troubleshooting, but need
some help in how to troubleshoot microprocessor circuits/ computers.
Are
there any techniques that help to determine if a processor circuit is
working properly other than just running it, and if there is no
troubleshooting software for it? Is it just a matter of checking to see
if
data is moving? How can you tell the data is correct? Any help in
troubleshooting these types of circuits is appreciated. Thanks.
B

Mostly it is done by board/module swapping.

Steps that can be used (but not often used as a scope is often required):

1/ Check all supply voltages
2/ Verify the clock signal
3/ Verify all inputs
4/ Verify activity on the busses

That was pretty much my line of thinking. Sometimes the "boss" doesn't
understand that though. Thanks.
Brian

Troubleshooting computers
 

On Sat, 10 Mar 2007 18:59:41 -0600 "KenB123" wrote in
Message id: :

I have a related question: how would you troubleshoot a motherboard which
resets CMOS to default every time a/c power is shut off, even with a fresh
battery?

Bad jumper plug for reset CMOS function?