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SK-AM64B: SK-AM64B serial console not responding to terminal

Part Number: SK-AM64B

Tool/software:

Hello,

I have a new SK-AM64B.  I am trying to boot into linux using the supplied WIC images.  I am connected to the usb-uart port on J11 and I receive boot messages from the processor.

Unfortunately, the processor does not respond to keystrokes from the terminal. I cannot stop the processor in u-boot. I cannot login at the login prompt.

Is there something special I need to do on this board to get bidirectional console IO?

  • Hello Peter,

    Are you following the steps in the SK-AM64B Quick Start Guide to set up serial communication?
    https://dev.ti.com/tirex/explore/node?a=7qm9DIS__LATEST&node=A__ALqhtJgGIUvD4HS9SggrMA__am64x-devtools__FUz-xrs__LATEST

    Regards,

    Nick

  • Yes, I think I followed the directions correctly,  115200 baud, 8N1.  I use these same terminal settings to talk to many other development boards.

  • I'm beginning to think this is due to the way that the processor is booting. Perhaps, u-boot is built with the console disabled in such a way that it cannot be interrupted by the console.  Also, when linux tries to start it seems to hang on processes that it is trying to start and maybe that is why I cannot type into the login prompt.

    It is unlikely that the usb-uart port is defective in such a way that it can send characters but not receive.

    I also found that the board appears on the local network.

    $ nmap -sP 192.168.1.1/24
    Starting Nmap 7.80 ( https://nmap.org ) at 2024-10-30 09:06 EDT
    Nmap scan report for am64xx-evm.lan (192.168.1.236)
    Host is up (0.00034s latency).

    and I was able to ssh into it.

    $ ssh root@192.168.1.236
    Linux am64xx-evm 6.6.32-k3-rt #1 SMP PREEMPT_RT Fri Aug  2 09:47:49 UTC 2024 aarch64

    The programs included with the Debian GNU/Linux system are free software;
    the exact distribution terms for each program are described in the
    individual files in /usr/share/doc/*/copyright.

    Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
    permitted by applicable law.

  • Hello Peter,

    Just to verify, are you booting with this filesystem image?
    https://www.ti.com/tool/download/PROCESSOR-SDK-LINUX-RT-AM64X
    tisdk-debian-trixie-rt-am64xx-evm.wic.xz  — 291076 K

    When I tested on the yocto image, terminal connectivity worked exactly as expected:

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    // on my Linux PC
    $ minicom -w -D /dev/ttyUSB1
    // terminal opens
    Welcome to minicom 2.8
    OPTIONS: I18n
    Port /dev/ttyUSB1, 17:53:12
    Press CTRL-A Z for help on special keys
    am64xx-evm login: [ 21.990070] platform led-controller: deferred probe pending
    [ 21.990127] platform 20000000.i2c: deferred probe pending
    am64xx-evm login: root
    [ 24.689257] audit: type=1006 audit(1713280219.894:2): pid=885 uid=0 old-auid=4294967295 auid=0 tty=(none) old-ses=4294967295 ses=1 res=1
    [ 24.690566] audit: type=1300 audit(1713280219.894:2): arch=c00000b7 syscall=64 success=yes exit=1 a0=8 a1=ffffdf0df5f8 a2=1 a3=1 items=0 ppid=1 pid=885 auid=0 uid=0 gid=0
    euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=(none) ses=1 comm="(systemd)" exe="/usr/lib/systemd/systemd-executor" key=(null)
    [ 24.690601] audit: type=1327 audit(1713280219.894:2): proctitle="(systemd)"
    root@am64xx-evm:~#
    XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

    I am reassigning your thread to another team member more familiar with the Debian version of the SDK.

    Regards,

    Nick

  • Peter,

    Perhaps, u-boot is built with the console disabled in such a way that it cannot be interrupted by the console.

    No the console is not disabled in U-Boot.

    Unfortunately, the processor does not respond to keystrokes from the terminal. I cannot stop the processor in u-boot. I cannot login at the login prompt.

    Please check the terminal program (for example, minicom in Linux, or TeraTerm in Windows) that its sw and hw flow control is indeed disabled.