Ignat
1
Basic Information:
Printer Model: Ender 3 Pro
MCU / Printerboard: BTT PI v. 1.2 / BTT SKR 1.4 Turbo
klippy.log
klippy.log (1.8 MB)
Describe your issue:I have SKR 1.4 Turbo and BTT PI works well with klipper trough USB.
I try to connect these trough UART, so I:
- edit /boot/BoardEnv.txt changing “console=display” to “console=serial” and reboot BTT PI
- build and flash klipper firmware changing Comunication interface from “USB” to “Serial (on UART0 P0.3/P0.2)” cause I use TFT plug
- connect BTT PI pins GND-PH0-PH1 (6-8-10) to SKR pins GND-TX0-RX0
- change klipper’s printer.cfg setting [mcu] serial: /dev/ttyS0
but I have communication error.
What can I do else or how to diagnose the problem?
Sineos
3
Hmm, strange. Your setup seems correct.
- RX and TX are crossed
- The pins on the BTT Pi seem correct with pins 6 (GND), 8 (TX), 10 (RX)
- Also the SKR 1.4 pins are P0.2 (TX), P0.3 (RX) are fine
Install setserial and provide the output of setserial -g /dev/ttyS[0123]
Edit:
Measure your cable for continuity. It would be stupid if it were something as simple as that.
1 Like
Ignat
4
Here it is:
setserial -g /dev/ttyS[01234]
/dev/ttyS0, UART: 16550A, Port: 0x0000, IRQ: 31
/dev/ttyS1, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS2, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS3, UART: unknown, Port: 0x0000, IRQ: 0
/dev/ttyS4, UART: unknown, Port: 0x0000, IRQ: 0
And GPIO lines 224, 225 witch are RX and TX are used by kernel:
gpioinfo |grep "22[4-5]"
line 224: unnamed kernel input active-high [used]
line 225: unnamed kernel input active-high [used]
Really, it is a a good advice. I’ll try it soon. And I want to try also TX3 RX3 of SKR to communicate.
Sineos
5
Looks good. Indeed, the UART0 seems active on the BTT Pi.
Unfortunately this brings me to “no further idea” as your setup seems sound.
1 Like
Ignat
6
I’ll let you know tomorrow about my success (or failure)
1 Like
Ignat
7
The solution from support is to power BTT Pi from SKR.
It works well. But I want to keep my PI on and to power the printer (and mcu) with SSR.
1 Like
Sineos
8
Thanks for passing on this solution.
I have to admit that this seems a strange solution.
