National Instruments PCI-232/2 用户手册

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页码 19
Using PCI Serial with Linux
12
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Troubleshooting and Common Questions
Error Codes
This section lists possible error codes and solutions.
Error Code
/dev/ttyS<
port number>: no such file or directory
Solution
The 
/dev/ttyS<
port number>
 does not exist in the 
/dev
 directory. Enter the 
following to create the device:
linux# cd /dev
linux /dev# ./MAKEDEV ttyS<
port number>
Error Code
Couldn't change i/o privilege level: Operation not permitted
Solution
The program requires superuser privileges. Either exit and log in as root, or enter 
the following:
linux$ su
Password: <
enter the root password>
linux# <
run the program>
Error Code
setserial: Cannot set serial info: Address already in use
Solution
Make sure you are entering the correct port address into 
setserial
. Also, make 
sure you are entering 
0x
 if you are specifying a hex number.
linux# setserial /dev/ttyS<
port number> uart 16550a port 
0x<
port address> irq <irq> ^fourport
Error Code
intenable: Can't open /dev/mem: Permission denied
Solution
The program requires superuser privileges. Either exit and log in as root, or enter 
the following:
linux$ su
Password: <
enter the root password>
linux# ./intenable <
PCI memory>