Find the answer to your Linux question:
Results 1 to 7 of 7
Hello All, I have installed the Fedora Core 5.0 on my x86 SBC. I have 6 COM ports on my board. The kernel sets up the first 4 without any ...
Enjoy an ad free experience by logging in. Not a member yet? Register.
  1. #1
    Just Joined!
    Join Date
    Jun 2006
    Posts
    4

    Question Fedora Core 5.0 - more than 4 serial ports


    Hello All,

    I have installed the Fedora Core 5.0 on my x86 SBC. I have 6 COM ports on my board. The kernel sets up the first 4 without any issues. When I try setting up the last 2, I get errors. I checked my .config file to verify I had support built in for more than 4 COM ports, this is true, I have up to 32 if I am reading it correctly. I had to create ttyS4 and ttyS5 using MAKEDEV in the /dev directoy because they did not previously exist. Then I used the setserial command as follows:
    setserial /dev/ttyS4 uart 16550a port 0x1a8 irq 9 ^fourport

    I did this for both ttyS4 and ttyS5, with different addresses of course.
    Both commands completed without errors. However, when I run the following command:
    setserial -a /dev/ttyS4
    I get the following error:
    /dev/ttyS4: No such device or address

    I did a google search for the error, but I have not been able to find anything that has helped. I also did a search for serial ports in this forum and did not see anything similar. If anyone has any suggestions, I would hugely appreciate any and all help. Thank you.

  2. #2
    Just Joined!
    Join Date
    Jun 2006
    Posts
    4

    Lightbulb solved problem

    I was able to solve my issue. Thanks anyway.

  3. #3
    RvH
    RvH is offline
    Just Joined!
    Join Date
    Aug 2006
    Location
    Netherlands
    Posts
    2

    Hi

    Hi

    I have the same problem.
    What can i do to fix this

    Thx Ron

  4. $spacer_open
    $spacer_close
  5. #4
    Just Joined! Oukki's Avatar
    Join Date
    Jul 2006
    Location
    Lapland, Finland
    Posts
    25
    Quote Originally Posted by val54321
    I was able to solve my issue. Thanks anyway.
    Hi val!

    Could you please share this knowledge with us? I've been struggling with the same problem for a rather long time now. For more info, see my previous thread "FC5: Changing/adding a serial port beyond ttyS3". Thanks!

  6. #5
    Just Joined!
    Join Date
    Jun 2006
    Posts
    4

    my solution for serial port issue

    I solved my problem by doing the following. Keep in mind, I am using Fedora Core 5, but the fix should work in other flavors of Linux as well.

    FC5 will only configure the first 4 serial ports by default. There is a config setting, CONFIG_SERIAL_RUNTIME_UARTS (or similar) which can be set to the number of serial ports to configure at system start up. Conveniently, this can be set by an option in /etc/grub.conf added to the kernel line:

    8250.nr_uarts=6

    This will setup /dev entries for the ports but either won't configure them or for our board the default config fails. So, to configure the ports manually, add the following to /etc/rc.local:

    setserial /dev/ttyS4 port 0x1A8 irq 9 uart 16550A baud_base 115200 setserial /dev/ttyS5 port 0x1A0 irq 9 uart 16550A baud_base 115200

    I hope that helps.

  7. #6
    RvH
    RvH is offline
    Just Joined!
    Join Date
    Aug 2006
    Location
    Netherlands
    Posts
    2
    Hi Val

    Many Thx for you'r respons.

    Ron

  8. #7
    Just Joined! Oukki's Avatar
    Join Date
    Jul 2006
    Location
    Lapland, Finland
    Posts
    25
    Hi val!
    Thank you VERY much for this information.
    Yet I thought I've tried everything, it never even crossed my mind to edit the grub.config -file.

    This will setup /dev entries for the ports but either won't configure them or for our board the default config fails. So, to configure the ports manually, add the following to /etc/rc.local...
    You must mean the rc.local file in /etc/rc.d/ directory with this one.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •