BTT SB2240 with error: MCU 'EBBCan' shutdown: ADC out of range

[KingCrab]

Hello,

I just switched from the original setup to CAN with a SB2240, but I'm unable to read the extruder temperature correctly (always -109). I use a 2-wire PT100, my switches are set S1 on, the three others off. This is my config:

[extruder] step_pin: EBBCan: PD0 dir_pin: !EBBCan: PD1 enable_pin: !EBBCan: PD2 gear_ratio: 50:10 #BMG Gear Ratio microsteps: 16 full_steps_per_rotation: 200 #200 for 1.8 degree, 400 for 0.9 degree rotation_distance: 22.4891434 nozzle_diameter: 0.400 filament_diameter: 1.750 heater_pin: EBBCan: PB13 sensor_type: Generic 3950 sensor_pin: EBBCan: PA3 control: pid pid_kp: 21.391 pid_ki: 1.240 pid_kd: 92.247 min_temp: 10 max_temp: 280 pressure_advance: 0.02 pressure_advance_smooth_time: 0.01 max_extrude_only_distance: 101

Hope anyone has an idea what I'm doing wrong here?

Thanks in advance

 

[KingCrab]

With the MAX31865 configured like this:

#sensor_type: Generic 3950
#sensor_pin: EBBCan: PA3

sensor_type: MAX31865
sensor_pin: EBBCan: PA4
spi_speed: 1000000
spi_bus: spi1
rtd_num_of_wires: 2
rtd_use_50Hz_filter: True
rtd_nominal_r: 100
rtd_reference_r: 430

the error changed to MCU 'EBBCan' shutdown: Thermocouple reader fault and in the klippy log I see those entries with a temperature of 940.7

Stats 1490.5: gcodein=0  mcu: mcu_awake=0.000 mcu_task_avg=0.000003 mcu_task_stddev=0.000003 bytes_write=6780 bytes_read=7443 bytes_retransmit=9 bytes_invalid=0 send_seq=335 receive_seq=335 retransmit_seq=2 srtt=0.001 rttvar=0.000 rto=0.025 ready_bytes=0 upcoming_bytes=0 freq=180003139 EBBCan: mcu_awake=0.001 mcu_task_avg=0.000007 mcu_task_stddev=0.000008 bytes_write=1654 bytes_read=5053 bytes_retransmit=0 bytes_invalid=0 send_seq=175 receive_seq=175 retransmit_seq=0 srtt=0.001 rttvar=0.000 rto=0.025 ready_bytes=0 upcoming_bytes=0 freq=64000241 adj=63999222  heater_bed: target=0 temp=20.4 pwm=0.000 sysload=0.20 cputime=102.557 memavail=747628 print_time=0.001 buffer_time=0.000 print_stall=0 extruder: target=0 temp=940.7 pwm=0.000

 

[Sandman50]

Do you have the EBB MCU declared in your printer.cfg?

[mcu]
canbus_uuid: ca9XXXxxx1bc3
#restart_method: command

[mcu EBBCan]
canbus_uuid: 41aXXXxxx3ad8

(example IDs...)

Try swapping out the thermistor - could also be a bad crimp, jumped wire, etc.

 

[KingCrab]

Do you have the EBB MCU declared in your printer.cfg?

[mcu]
canbus_uuid: ca9XXXxxx1bc3
#restart_method: command

[mcu EBBCan]
canbus_uuid: 41aXXXxxx3ad8

(example IDs...)

Try swapping out the thermistor - could also be a bad crimp, jumped wire, etc.

I only have the uuid in my sb_canbus.cfg. Printer.cfg contains serial: /dev/serial/by-id/... .

 

[Sandman50]

Pretty sure you need to have the can mcu call out, not serial callout.

Klipper needs to know how to communicate. Since you are using CAN, need to tell klipper to communicate via can.

 

[B_white_80]

Any Solution?

 

[KingCrab]

I gave up on the SB2240 and ordered a SB2209 with RP2040. The PT100 did work out of the box, but the board is losing its firmware on every reset. I'm thinking of switching back to regular wiring... :-(