Linux and PCI-485/8. Write failed:Input/Output error

[cocteau_tt]

i am running red hat linux and installed my pci-485/8 serial card. actually, the machine is dual boot with windows nt 4.0 and the card works fine under nt. i followed all the instructions in the ni document "notes to users" entitled "using pci serial with linux". when i finally run serialtest i just get the error message above: Write failed:Input/output error.

not much to go on. any advice???

[Ketan Vyas]

There are few things that we can try to trouble shoot this problem.
Try uninstalling driver for Win NT completely and reinstalling driver for Linux and see whether that solves the problem.
If that doesn't solve the problem then try using a different Linux machine ( if you have access to ) for the same card. The card works under Win NT that means card is fine and there is no hardware issue associated with this problem.
Try recompiling your serialtest.c :
Enter the following to recompile serialtest.c and rerun serialtest.
(Also, the source code for serialtest is available for editing and viewing
at serialtest.c, provided in the PCI-SERIAL directory.)
linux PCI-SERIAL# gcc serialtest.c -o serialtest
linux PCI-SERIAL# ./serialtest < receive port numbe
r>
< transmit port number>
If serialtest hangs:
Make sure the interface is seated correctly and tighten the screw that holds
the interface in place. Also, make sure the cables are attached to the correct
ports. In some cases, serialtest hangs if the transceiver modes
(PCI-485) are not set. Try setting both transmit and receive ports to
transceiver mode 0 (Four-Wire Mode).
linux# ./rs485 < transmit port number> 0
linux# ./rs485 < receive port number> 0
linux# ./serialtest < receive port number> < transmit port number>

See the attached file for more information.