Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 37
Default 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


  #2   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 590
Default 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


  #3   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 1,245
Default 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.



  #4   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 2
Default 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.







  #5   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 1,245
Default 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?





  #6   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 2
Default 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?





  #7   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 1,245
Default 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.



  #8   Report Post  
Posted to sci.electronics.repair
CJT CJT is offline
external usenet poster
 
Posts: 1,155
Default 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 .
  #9   Report Post  
Posted to sci.electronics.repair
CJT CJT is offline
external usenet poster
 
Posts: 1,155
Default 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 .
  #10   Report Post  
Posted to sci.electronics.repair
external usenet poster
 
Posts: 37
Default 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




  #11   Report Post  
Posted to sci.electronics.repair
JW JW is offline
external usenet poster
 
Posts: 139
Default 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?
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Very OT - Computers Corinne Home Repair 118 July 24th 06 12:07 PM
Very OT - Computers (A BIG Thanks Everyone) Corinne Home Repair 30 July 15th 06 11:23 PM
repairing old computers orange Electronics Repair 3 July 20th 05 04:21 AM
OT- Do computers think? Jeff Wisnia Metalworking 2 January 12th 05 12:14 AM


All times are GMT +1. The time now is 01:15 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"