I am trying to enable uart on the beaglebone ai64.
Here are my steps:
Pull device tree repo and checkout v5.10.x-ti-unified branch
I see that there is already a BONE-UART1.dts and linked to the k3-j721e-beagleboneai64-bone-buses.dtsi for P9_24 and P9_26.
Then make and make install_arm64
Add “fdtoverlays /overlays/BONE-UART1.dtbo” to extlinux.conf
Reboot then sudo beagle-version | grep UBOOT and see “UBOOT: Loaded Overlay:[BONE-UART1.kernel]”
After that I use my logic analyzer to see if P9_24 is outputting any signals and I don’t capture any output. import serial
ser = serial.Serial(port=“/dev/ttyS4”, baudrate=9600, timeout=10)
When I also run setserial -g /dev/ttyS I get output
/dev/ttyS0, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS1, UART: 8250, Port: 0x0000, IRQ: 15
/dev/ttyS2, UART: 8250, Port: 0x0000, IRQ: 30
/dev/ttyS3, UART: 8250, Port: 0x0000, IRQ: 31
/dev/ttyS4, UART: 8250, Port: 0x0000, IRQ: 32
/dev/ttyS5, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS6, UART: 8250, Port: 0x0000, IRQ: 33
I find it odd that they all have the same port address.
Are you sure is it /dev/ttyS4 ?
Depending on the order of enumeration it might be different.
I think there is a udev script that creates symbolic links in /dev/bone / You can in a udev script refer to the hardware address to create a symbolic link that does not depend on enumeration order I think. I do something like that for my 6 CAN cape so the actual device listed in networks matchs the physical CAN ports used, rather than numbering from 0.
At worst case, try your python scripts on all UARTS and check the I/O.