A8N-SLI-serial port erratic

  • Thread starter Thread starter mogur2
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mogur2

For some reason the one serial port on this board behaves erratically. I only have one
application requiring that port. At times after a restart, that program (a weather
station) reports that it cannot contact the sensors which report via the rs232 port.

Sandra pro shows that port active, but not for the proper app. I sometimes have to
restart two or three times before it will work properly.

On this board, the port is connected via a cable from the board to an external connector,
not a direct connection.

My question, could the cable be bad, or the cable from the mb to the external connector?

BTW, I tried to use the many USB 2.0 connectors but the one USB to Serial connector did
not connect properly and the data was often delayed.

Any suggestions?

Thanks,
 
mogur2 said:
For some reason the one serial port on this board behaves
erratically. I only have one application requiring that port.
At times after a restart, that program (a weather station)
reports that it cannot contact the sensors which report via
the rs232 port.

Sandra pro shows that port active, but not for the proper app.
I sometimes have to restart two or three times before it will
work properly.

On this board, the port is connected via a cable from the board
to an external connector, not a direct connection.

My question, could the cable be bad, or the cable from the mb
to the external connector?

BTW, I tried to use the many USB 2.0 connectors but the one USB
to Serial connector did not connect properly and the data was
often delayed.

Any suggestions?

Thanks,
Click to expand...

If you are able to transmit and receive some data via RS-232,
then the cable is OK. If the cable had an open circuit, or was
wired incorrectly (there are two different standards for
adapter cables), it would not function at all.

A previous poster had a problem with serial I/O on his A8N-E.
Both of your boards use ITE8712F Super I/O chip, to drive
the serial port. It could be, that there is a problem with
the enumeration of the logic block, with the programming of
the registers for the 16C550 compatible logic blocks, or the
like. One of the unique symptoms in his case, is the CPU
goes to 100%, when he runs Hyperterminal. That almost
suggests an interrupt condition is being triggered
continuously for some reason.

File a report with Asus tech support, so that their BIOS
maintenance people can have a look at it. The more people
who file reports, the sooner it gets fixed.

If you are the experimenter type, try reducing the interconnect
to just RXD and TXD. See if flow control is involved some
how. I have a handful of bare connectors bought from an
electronics store, and I've custom wired the odd connector
for doing experiments like this. (Like a male-female connector
pair, with just TXD, RXD, GND, SHIELD_GND, wired through.)

Rather than debug this problem, it may be easier to just get
a PCI RS-232 card. Here is one for $8.00.

http://www.newegg.com/Product/Product.asp?Item=N82E16815124010

HTH,
Paul
 
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