HELP - Octoprint & RPI3 GPIO bizarre response codes  

HELP - Octoprint & RPI3 GPIO bizarre response codes

Dear friends,

I'm connecting a brand new Prusa i3 MK3S printer to a raspberry pi 3B+ via GPIO. I am not able to connect it. I have checked the cables and I have followed the PRUSA tutorial but I am unable to connect them. Anyway, I do see that there's communication between the raspberry and the printer.

Here is the first log I saw when connecting:

Connecting to: /dev/ttyAMA0
Changing monitoring state from "Offline" to "Opening serial port"
Connected to: Serial<id=0x6a931bf0, open=True>(port='/dev/ttyAMA0', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
Starting baud rate detection...
Changing monitoring state from "Opening serial port" to "Detecting baudrate"
Trying baudrate: 115200
Send: N0 M110 N0125
Baudrate test retry #1
Send: N0 M110 N0125
Baudrate test retry #2
Send: N0 M110 N0125
Baudrate test retry #3
Recv: e\x00cho:Unknown command:0"<��O���������y�=�����\x7f�|�k�������[+������\x7f\x1eb?>�o_rd-u�O�ukj�:U���������;����;t'�Z���[ok
Send: N0 M110 N0125
Recv: uv{oz:M�\x7fe�u{��W)k�����1�����������������X Last Line: 0
Recv: Resend: 1
Recv: ok
Changing monitoring state from "Detecting baudrate" to "Operational"
Send: N0 M110 N0125
Communication timeout while idle, trying to trigger response from printer. Configure long running commands or increase communication timeout if that happens regularly on specific commands or long moves.
Send: N1 M11539
Recv: Error:No Line�������with�,�{����l����}\x7fu����]�����������{�o�����\x7f��{o��o-��>o��������o�[<�y�����_��=�X:io��o��e���������q���+�����]+����U.���� �2j�kk�ecyK��k�owo�coomqnf: "\x1a/~W.m~l\x14"()"(2)
See octoprint.log for details
Changing monitoring state from "Operational" to "Offline (Error: See octoprint.log for details)"
Connection closed, closing down monitor

And in another try I did, this is the output from serial.log:

2019-08-10 22:20:31,902 - Changing monitoring state from "Connecting" to "Offline"
2019-08-10 22:20:34,820 - Connecting to: /dev/ttyAMA0
2019-08-10 22:20:34,833 - Changing monitoring state from "Offline" to "Opening serial port"
2019-08-10 22:20:34,838 - Connected to: Serial<id=0x6977cb30, open=True>(port='/dev/ttyAMA0', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=10.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
2019-08-10 22:20:34,838 - Changing monitoring state from "Opening serial port" to "Connecting"
2019-08-10 22:20:34,854 - Send: N0 M110 N0125
2019-08-10 22:20:41,022 - Recv: u��k��k�
��mX�i�"����m�-ook
esjo>U������komm\����=���".2"(2)
2019-08-10 22:20:41,025 - Recv: ok
2019-08-10 22:20:41,038 - Changing monitoring state from "Connecting" to "Operational"
2019-08-10 22:20:41,058 - Send: N0 M110 N0125
2019-08-10 22:21:33,213 - Communication timeout while idle, trying to trigger response from printer. Configure long running commands or increase communication timeout if that happens regularly on specific commands or long moves.
2019-08-10 22:21:33,220 - Send: N1 M11539
2019-08-10 22:22:03,242 - Communication timeout while idle, trying to trigger response from printer. Configure long running commands or increase communication timeout if that happens regularly on specific commands or long moves.
2019-08-10 22:22:03,253 - Send: N2 M2118

These are the software versions:

OctoPrint Version: 1.3.11
Prusa Firmware: 3.7.2-2363
Raspberry Pi OS: Octopi 0.16.0

Any help is appreciated.

Best regards.