Using QNX 4.25D with the TL-SBC 6620 (Pentium III 550mhz) passive backplane
with integrated LAN card disabled (replaced with CORMAN 10/100).
Experiencing unexplained system re-starts whereby the computer will actually
reboot itself. Has anyone had any similar experiences? Any ideas on how to
trouble shoot this?
Dave Marker
Interpro Technology, Inc.
interprotech@ameritech.com
I would suggest looking for power supply problems. I had similar symptoms
once with a PC/104 SBC (i.e no backplane) because the power connector wasn’t
particularly good. It wasn’t obvious and the only reason I have for blaming
the connector was that after we replaced it, the problem went away…
If your power supply is underrated for the system (Pentim III’s can draw
quite a lot of current), this might cause a “brownout”.
Good luck.
Tristan Crees B.C.S.E
Robotics Engineer
International Submarine Engineering (http://www.ise.bc.ca)
1734 Broadway St. Port Coquitlam BC Canada V3C 2M8
“David F. Marker” <interprotech@ameritech.net> wrote in message
news:94hraq$l6b$1@inn.qnx.com…
Using QNX 4.25D with the TL-SBC 6620 (Pentium III 550mhz) passive
backplane
with integrated LAN card disabled (replaced with CORMAN 10/100).
Experiencing unexplained system re-starts whereby the computer will
actually
reboot itself. Has anyone had any similar experiences? Any ideas on how
to
trouble shoot this?Dave Marker
Interpro Technology, Inc.
interprotech@ameritech.com
I would tend to agree with that. I have no experience with the particular board,
but a lot of embedded PCs have a Voltage monitor chip driving the reset line.
This chip prevents erroneous operation of the PC if the power supply volts goes
outside of a safe range for the device. If you have any excess resistance in the
power supply feeding the processor card (specifically the 5V line), sometimes
this chip might hold the processor in reset. The trick is that holding the
processor in reset immediately reduces the load on the 5V rail, so up come the
volts and away it goes again as if nothing has happened - and you go looking for
a software problem!!!
This is quite a common problem. I once was provided with a sizable embedded
system that drew around 40A on the 5V rail. The connections to the PSU were
through wire lugs riveted to a copper-clad PCB. This might have been fine when
it was new but once it was a few months old it would not run until these
connections were replaced with something better.
Tristan Crees wrote:
I would suggest looking for power supply problems. I had similar symptoms
once with a PC/104 SBC (i.e no backplane) because the power connector wasn’t
particularly good. It wasn’t obvious and the only reason I have for blaming
the connector was that after we replaced it, the problem went away…If your power supply is underrated for the system (Pentim III’s can draw
quite a lot of current), this might cause a “brownout”.Good luck.
–
Tristan Crees B.C.S.E
Robotics Engineer
International Submarine Engineering (> http://www.ise.bc.ca> )
1734 Broadway St. Port Coquitlam BC Canada V3C 2M8“David F. Marker” <> interprotech@ameritech.net> > wrote in message
news:94hraq$l6b$> 1@inn.qnx.com> …
Using QNX 4.25D with the TL-SBC 6620 (Pentium III 550mhz) passive
backplane
with integrated LAN card disabled (replaced with CORMAN 10/100).
Experiencing unexplained system re-starts whereby the computer will
actually
reboot itself. Has anyone had any similar experiences? Any ideas on how
to
trouble shoot this?Dave Marker
Interpro Technology, Inc.
interprotech@ameritech.com