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    Accessing usb uart from linux

    Hi
    I have a custom made legacy power pc board which has a dedicated serial (DB9) and UART-USB bridge from FTDI. I am able to send data from uboot prompt in both to DB9 and UART-USB(accessed via VCOM in PC). When I run an application (linux), I can see data through DB9 (by sending data stream to tty0). However I am unclear about sending the same data stream over UART-USB. I guessed as tty1, but the system crashes. Any clues?

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    Re: Accessing usb uart from linux

    Try /dev/ttyUSB0 or /dev/ttyUSB1.

    Brian.
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    Re: Accessing usb uart from linux

    Hi,

    I could not locate ttyUSB1 in the dev directory. Perhaps the preloaded os does not contain this driver.



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    Re: Accessing usb uart from linux

    Did you try lusb to list all detected USB devices on your computer ? In addition, are you aware that each USB/Serial adaptor has its own device driver, and the most commonly used are not installed by default at some Linux distros ?
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    Re: Accessing usb uart from linux

    Hi andre
    I did try and could not locate the driver. This preloaded linux does not have this driver in place. Now, what is the workaround? FTDI driver has been installed in my host PC.



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    Re: Accessing usb uart from linux

    Show us what 'lsusb tells you.

    If you can see the UART in the list, type this:

    "lsusb -v -s xxx:yyy" where xxx:yyy is the Bus number and the Device number (not the hex ID numbers) then show us the result.

    "lsusb" means 'LiSt USB devices", the '-v' means be verbose and '-s' list the descriptor and information table for the named device. As far as I know, all FTDI drivers have been built into the Linux kernel for several years now so you probably don't need any additional drivers.

    Brian.
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    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.



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    Re: Accessing usb uart from linux

    hi betwixt

    Surely I will try the option you suggested. In the meantime, I would like to inform that originally this board did not have an USB interface (it had only UART). FTDI chip was added later as a piggy back to interface a PC due to legacy issues.



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