I’ve been working on a Beaglebone Green Wireless for a few weeks and have been using USB FTDI for serial communication. I now need to use the onboard UART1, UART2 and UART4.
I have been googling and reading through all the topics on the Forum and ended up wrecking my image twice so I really need help.
I’m using the latest bone-debian-9.5-iot-armhf-2018-10-07-4gb.img
When I try using config-pin 911 uart I get a message that P9_11 pinmux file not found. Pin has no cape: P9_11
I have also tried updating the uEnv file with the following
This caused my BBG to throw errors on boot and I wasn't able to access the device
After a rebuild I made the above change to uEnv.txt and then added the overlays but on boot I got errors that they could not be loaded.
Try adding them under Additional custom capes part not the Override cape with EEPROM
###Additional custom capes
I ended up doing the following
Updating Uboot to latest version
Updating kernel to latest version
Unblock Uboot Overlays - apparantly the eMMC can block them…
sudo dd if=/dev/zero of=/dev/mmcblk1 bs=1M count=10
Updating the Overlays
sudo apt update
sudo apt install --only-upgrade bb-cape-overlays
Adding in the additional capes to uEnv.txt
I can now get access to dev/tty04 and send / receive. I now need to work out why when I Open and Close the serial port and try to reopen it hangs on the Open command. I have to reboot each time I try my application… It works fine on dev/ttyUSB0 ftdi lead.