Random firmware resets

R_Klauco

I am using 0.92.8 version of firmware.I love the features and I am generaly satisfied with the SW.However, lately I started to experience a strange problem.I have direct serial connection to my Melzi board from Banana Pi. This works no problem. I printed hundreds of hours worth of prints.Lately, however, I start to have failures - Octoprint complains about "Unhandled firmware exception".So, I checked what's going on - I am sending Gcode to the board as usual and on random places all of a sudden the board resets.I can see the log - sent command and instead of OK, I can see the repetier FW initialization log.And, as soon as the timeout hits, Octoprint starts to resend the command, but this is unsuccessfull, of course, as Repetier is expecting command number 1 and I'm sending command number 3000...I have not seen a common pattern for now - even when I try to re-print the same thing, usualy all prints OK.Once this happened twice in a row.I checked all the power connections for the board (powered by the printer, not by USB or anything).But it's very difficult for me to identify possible short-term power outage :(Any hints/tips from someone who experienced similar behaviour?

R_Klauco

Today it happened again, this is the serial log from the moment:
Recv: ok 13027
Send: N13029 G1 X50.058 Y93.867 E4.10485108
Recv: ok 13028
Send: N13030 G1 X50.058 Y94.733 E4.15007102
Recv: start
Recv: Info:Autoleveling enabled
Recv: Transformation matrix: 1.000000 -0.000000 -0.000257 0.000000 1.000000 -0.000632 0.000257 0.000632 1.000000
Recv: Free RAM:12597
Recv: SelectExtruder:0
Recv: FlowMultiply:100
...

R_Klauco

And right after restart, while only heating the extruder and bed:

Recv: T:232.80 /245 B:84.55 /94 B@:255 @:230
Recv: T:235.40 /245 B:84.55 /94 B@:255 @:230
Recv: start
Recv: Info:Autoleveling enabled
Recv: Transformation matrix: 1.000000 -0.000000 -0.000257 0.000000 1.000000 -0.000632 0.000257 0.000632 1.000000
Recv: Free RAM:12597
Recv: SelectExtruder:0
Recv: FlowMultiply:100
Recv: SD init fail
Changing monitoring state from 'Operational' to 'Closed'
Connecting to: /dev/ttyS3
Changing monitoring state from 'Offline' to 'Opening serial port'
Connected to: Serial<id=0xa08ebd30, open=True>(port='/dev/ttyS3', baudrate=115200, bytesize=8, parity='N', stopbits=1, timeout=30.0, xonxoff=False, rtscts=False, dsrdtr=False), starting monitor
Changing monitoring state from 'Opening serial port' to 'Connecting'
Send: N0 M11035
Recv: ok
Changing monitoring state from 'Connecting' to 'Operational'
Send: N1 M11539</span>
Recv: ok 1
Recv: FIRMWARE_NAME:Repetier_0.92.8 FIRMWARE_URL:https://github.com/repetier/Repetier-Firmware/ PROTOCOL_VERSION:1.0 MACHINE_TYPE:Mendel EXTRUDER_COUNT:1 REPETIER_PROTOCOL:3
Recv: Printed filament:587.72m Printing time:6 days 7 hours 22 min
Recv: PrinterMode:FFF
Send: N2 M105*37
Recv: ok 2