I've tested my probe is working by doing a loop back test (Connecting its TX to it RX, starting minicom and seeing the chars I type echoed back to me.)
On the pi
And I can see GPIO15 changing state when I type in minicom on my desktop which is connected to the pi via the debug probes uart.
Next I start minicom on the pi
When I type in minicom on the pi the chars show in minicom on my desktop and vi versa.
If I reboot the pi I see nothing in minicom.
I'm expecting to see the kernel messages, as it boots, and then get a log in prompt.
Interestingly /boot/firmware/cmdline.txt has the following:
Suggesting that the console output is going to serial0 which is a symlink to /dev/ttyAMA10
So I changed the /boot/firmware/cmdline.txt to the following:
And got a login prompt!
On the pi
Code:
ben@raspberrypi:~ $ ls -la /dev/serial0 lrwxrwxrwx 1 root root 8 Aug 1 18:45 /dev/serial0 -> ttyAMA10ben@raspberrypi:~ $ ls -la /dev/ttyAMA*crw-rw---- 1 root dialout 204, 64 Aug 1 18:52 /dev/ttyAMA0crw-rw---- 1 root dialout 204, 74 Aug 1 18:47 /dev/ttyAMA10ben@raspberrypi:~ $ Code:
ben@raspberrypi:~ $ pinctrl poll 1515: hi // GPIO15+2185984us15: lo // GPIO15+6us15: hi // GPIO15+12us15: lo // GPIO15+14us15: hi // GPIO15+14us15: lo // GPIO15+4us15: hi // GPIO15Code:
minicom -D /dev/ttyAMA0If I reboot the pi I see nothing in minicom.
I'm expecting to see the kernel messages, as it boots, and then get a log in prompt.
Interestingly /boot/firmware/cmdline.txt has the following:
Code:
console=serial0,115200 console=tty1 root=PARTUUID=06a32e34-02 rootfstype=ext4 fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consolesSo I changed the /boot/firmware/cmdline.txt to the following:
Code:
console=ttyAMA0,115200 console=tty1 root=PARTUUID=06a32e34-02 rootfstype=ext4 fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consolesCode:
[ 0.792774] brcm-pcie 1000110000.pcie: link downDebian GNU/Linux 12 raspberrypi ttyAMA0My IP address is 192.168.1.188 fe80::44b4:c632:1534:a1caraspberrypi login: benPassword: Linux raspberrypi 6.12.25+rpt-rpi-2712 #1 SMP PREEMPT Debian 1:6.12.25-1+rpt1 (2025-04-30) aarch64The programs included with the Debian GNU/Linux system are free software;the exact distribution terms for each program are described in theindividual files in /usr/share/doc/*/copyright.Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extentpermitted by applicable law.Last login: Fri Aug 1 19:07:17 BST 2025 on tty1Wi-Fi is currently blocked by rfkill.Use raspi-config to set the country before use.ben@raspberrypi:~$ Statistics: Posted by JaminCat — Fri Aug 01, 2025 6:08 pm