Testing "pull/7180".
Took two RPi5's, made a crossover connection for uart0 (pin8-pin10, pin10-pin8). Started a serial terminal cutecom on one RPi5 and used the other for testing.
1. Using Raspberry Pi Imager, flashed the latest "Raspberry Pi OS Lite 64-bit trixie 4 Dec 2025" to the SD card. Inserted it, booted, configured SSH, Ethernet, WiFi. OK, everything works.
Linux version - 6.12.47+rpt-rpi-2712 #1 SMP PREEMPT Debian 1:6.12.47-1+rpt1 (2025-09-16) aarch64 GNU/Linux
Firmware version: Wed 5 Nov 17:37:18 UTC 2025 (1762364238)
2. Copied the "uart0-rts485.dtbo" file (see first post or attachment) to the "/boot/firmware/overlays" folder. Added "dtoverlay=uart0-rts485" to config.txt. Rebooted.
Connected via SSH, entered "echo "1" > /dev/ttyAMA0" - received "31 0D 0A" on the RPi5 with cutecom. OK, it works.
3. Entered "sudo rpi-update pulls/7180" - everything downloaded and updated. Rebooted.
Linux version - 6.12.62-v8-16k+ #1 SMP PREEMPT Thu Dec 18 11:32:14 UTC 2025 aarch64
4. In config.txt, replaced with "dtoverlay=uart0" (not 485!). Rebooted.
Connected via SSH, entered "echo "1" > /dev/ttyAMA0" - received "31 0D 0A" on the RPi5 with cutecom. OK, it works.
5. In config.txt, replaced with "dtoverlay=uart0-rts485". Rebooted.
Connected via SSH, entered "echo "1" > /dev/ttyAMA0" - Pi HANGS!, and reboots itself after 8-10 seconds. On the RPi5 with cutecom, received "31", i.e., one byte was transmitted, after which the problems started.
Questions:
1. Does the modified uart driver not work on RPi5?
2. Is my overlay incorrect? What should it be?
3. Did I set up the testing incorrectly? How should it be done?
Took two RPi5's, made a crossover connection for uart0 (pin8-pin10, pin10-pin8). Started a serial terminal cutecom on one RPi5 and used the other for testing.
1. Using Raspberry Pi Imager, flashed the latest "Raspberry Pi OS Lite 64-bit trixie 4 Dec 2025" to the SD card. Inserted it, booted, configured SSH, Ethernet, WiFi. OK, everything works.
Linux version - 6.12.47+rpt-rpi-2712 #1 SMP PREEMPT Debian 1:6.12.47-1+rpt1 (2025-09-16) aarch64 GNU/Linux
Firmware version: Wed 5 Nov 17:37:18 UTC 2025 (1762364238)
2. Copied the "uart0-rts485.dtbo" file (see first post or attachment) to the "/boot/firmware/overlays" folder. Added "dtoverlay=uart0-rts485" to config.txt. Rebooted.
Connected via SSH, entered "echo "1" > /dev/ttyAMA0" - received "31 0D 0A" on the RPi5 with cutecom. OK, it works.
3. Entered "sudo rpi-update pulls/7180" - everything downloaded and updated. Rebooted.
Linux version - 6.12.62-v8-16k+ #1 SMP PREEMPT Thu Dec 18 11:32:14 UTC 2025 aarch64
4. In config.txt, replaced with "dtoverlay=uart0" (not 485!). Rebooted.
Connected via SSH, entered "echo "1" > /dev/ttyAMA0" - received "31 0D 0A" on the RPi5 with cutecom. OK, it works.
5. In config.txt, replaced with "dtoverlay=uart0-rts485". Rebooted.
Connected via SSH, entered "echo "1" > /dev/ttyAMA0" - Pi HANGS!, and reboots itself after 8-10 seconds. On the RPi5 with cutecom, received "31", i.e., one byte was transmitted, after which the problems started.
Questions:
1. Does the modified uart driver not work on RPi5?
2. Is my overlay incorrect? What should it be?
3. Did I set up the testing incorrectly? How should it be done?
Statistics: Posted by YurgenGz — Wed Dec 24, 2025 6:52 pm