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udev rules error on BBB

ramanc51

Hi all

             In my BBB i written udev rule 99-usb-serial.rules at /etc/udev/rules.d to fix my usb-serial converter ttyUSB0 name as static(e.g printer), but this rules not create symlink as i given below, alos i saw error that unable to open '/sys/udev/ttyUSB0', is there glue to resolve this error?

 

my 99-usb-serial.rules

 

SUBSYSTEMS=="usb-serial", MODE="0666", ATTR{idVendor}=="0403", ATTR{idProduct}=="6001", SYMLINK+="printer"

 

Error

parse_file: reading '/etc/udev/rules.d/99-usb-serial.rules' as rules file

udev_rules_new: rules use 197880 bytes tokens (16490 * 12 bytes), 32369 bytes buffer

udev_rules_new: temporary index used 60680 bytes (3034 * 20 bytes)

unable to open device '/sys/dev/ttyUSB0'

debian@beaglebone:~$

 

Note:

        But i am able to open this device as /dev/ttyUSB0 only by my another java application on same BBB, but not as a printer

  • in reply to bwelsby

    Thanks Brain, i solved it by adding symlink names with column separated as follows 

     

       System.setProperty("gnu.io.rxtx.SerialPorts", "/dev/Printer:/dev/Display");

             

    but i think we can solve it as follows also by script

     

    java -Dgnu.io.rxtx.SerialPorts=/dev/printer:/dev/dispaly

  • in reply to ramanc51

    Great,  Yes and I have just found this too in the FAQ - Rxtx

     

    You can specify the available ports by 

     System.setProperty("gnu.io.rxtx.SerialPorts", portFileNames);

    where the file names of the ports are separated by File.pathSeparator.

  • in reply to bwelsby

    Brain, now i am facing another issue that, when job get done by my java app, the device is get disconnected and then appeared with new portname e.g ttyUSB1/2 automatically in /dev directory, now  i send command to that device, job is not get done because port is changed my app assign this device with same symlink that correscopnds to another ttyUSB1/2 on startup, if i restart my app then works once then same issue comes, i don't know why this behavior on BBB, my job is to print token using small thermal printer, this thermal printer is interfaced with BBB through USB-Serial converter(Prolific-PL2303), Do you have any idea or clue about this issue?