Basic Information: Printer Model: Ender 3 V3 SE MCU / Printerboard: CR4NS200320C13 klippy.log klippy (1).log (421.4 KB) Describe your issue: Hey all, I’ve been running klipper on my ender v3 se for the past few weeks and its been amazing, but I havent been able to get my rpi camera to work, …

Did you have a look here How-To Trouble-Shoot ? Good luck, hcet14

Reflash your board according to the relevant instructions Use the dmesg tool to check if your board registers properly in Linux Check ls /dev/serial/by-id/*

Hey @Sineos , appreciate the help. Still stuck though. I have tried reflashing a couple times. Seems it may be fine based on your last two points? When I run ls /dev/serial/by-id/* I get /dev/serial/by-id/usb-1a86_USB_Serial-if00-port0 I have also attached the dmesg output, which seems to be fine…

Yeah, I think something else weird is going on. Thanks hcet!

you have the serial wrong in the printer.cfg [mcu] serial = /dev/ttyUSB0 restart_method = command additionally you flashed the board with the wrong baud rate: CONFIG_SERIAL_BAUD=115200 Your rpi camera has absolutely nothing to do with Klipper, reflashing your board makes no sense

My understanding is that I can use either ttyUSB0 or the other serial. In any case, I have tried both and neither resolve the issue. As for baud rate, this is a setting specific to this ender board. I ran into this problem when I set up klipper initially and changing it from 250000 to 115200 fixed …

Flash again with following settings: STM32F103 “28KiB bootloader” serial (on USART1 PA10/PA9) “Enable extra low-leverl configuration options” and “Disable SWD on startup” copy klipper.bin to a SD rename it to something unique (not used before, only lowercase letters but ending in .bin) turn on the…

Hey @Sineos , thanks for this. Still not working. Posting new logs here, getting the same error. I also just started everything over from scratch, this time using the mainsail OS image for RPI (versus kiauh) and still getting the same result. klippy (3).log (113.7 KB)

Sorry, cannot offer any more guidance. Your error is a low level error of Linux that it cannot open your board as a serial device as it does not respond like expected. This typically has two reasons: First and foremost and board that is not correctly flashed Wiring issues between board and SBC, …

[image] wewu: As for baud rate, this is a setting specific to this ender board. I ran into this problem when I set up klipper initially and changing it from 250000 to 115200 fixed the issue entirely. For sake of argument, I just tried it at 250000 again and returned the same result. @huhen us…

Reflashed klipper (ender v3 se) and now getting mcu error

General Discussion

Sineos January 21, 2024, 6:45pm 3

Reflash your board according to the relevant instructions
Use the dmesg tool to check if your board registers properly in Linux
Check ls /dev/serial/by-id/*

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Reflashed klipper (ender v3 se) and now getting mcu error

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