Stepper driver cooling fan control

[wary osprey]

Is there an already made option in RATOS for controlling a cooling fan depending on the Octopus / Pi / steppers temperature ?

[cloud nexus]

Unfortunately there is no way currently to get the stepper driver temp. There is already the controller fan that only turns on when the stepper drivers are on. If you specifically want other fans to only turn on when MCU or PI is at a certain temp you can create that with https://www.klipper3d.org/Config_Reference.html#temperature_fan

[wary osprey]

tnx a lot mate, i'll look into that .

[wary osprey]

i think i've managed to get the temps and also added a fan

the code is crude, i'm no expert, but it seems to work

[temperature_sensor tmc2209_stepper_x]
sensor_type: temperature_host
min_temp: 10
max_temp: 100

[temperature_sensor tmc2209_stepper_y]
sensor_type: temperature_host
min_temp: 10
max_temp: 100

[temperature_sensor tmc2209_stepper_z]
sensor_type: temperature_host
min_temp: 10
max_temp: 100
[temperature_sensor tmc2209_stepper_z1]
sensor_type: temperature_host
min_temp: 10
max_temp: 100
[temperature_sensor tmc2209_stepper_z2]
sensor_type: temperature_host
min_temp: 10
max_temp: 100

[temperature_fan stepper_driver]
pin: PA8
max_power: 1.0
shutdown_speed: 0.0
cycle_time: 0.0001 #10 kHz PWM signal
hardware_pwm: False
kick_start_time: 0
sensor_type: temperature_host
min_temp: 0
max_temp: 70
target_temp: 50
max_speed: 0.7
min_speed: 0.0
control: pid
pid_Kp: 2.0 ;40
pid_Ki: 5.0 ;0.2
pid_Kd: 0.5 ;0.1
pid_deriv_time: 2.0

needs proper devlopment ...............

[civic plover]

Show us the code! 😄

[wary osprey]

it's above..........but i could be very wrong as well, but the temperatures do match with my thermal camera

[civic plover]

Oh, so you're saying: sensor_type: temperature_host actually works, with no klipper modifications? 🤨

[wary osprey]

yup, it's running right now............the only problem is defining which temperature_host is used

[civic plover]

it shouldn't be valid in that section

temperature_host is the pi

[wary osprey]

i guess it's the last one

[civic plover]

it's the raspberry pi

[wary osprey]

LOL

[civic plover]

I've got no idea why that config doesn't result in an error though

sensor_type shouldn't be valid in [tmc2209] sections.

[wary osprey]

i'll try cooling the pi only , see if it differs from the other temps

[civic plover]

I was very curious because as far as i know, you can't read the temperature out of the tmc2209

All you get is an error state and a warning state that you've gotta monitor.

[wary osprey]

i'm reading the datasheet atl, got 3 temp trigger points, correst

[civic plover]

That's not a klipper limitation, it's a TMC driver limitation

Yeah

[wary osprey]

well, that's sad............at least i can cool the pi

i'll add a sensor in the cooling duct exit's for the drivers.......

for the moment i changed it to temperature_mcu to cool complete board

and that does not work, so why does the temperature_host work and not temperature_mcu ???

[civic plover]

might wanna ask that on the klipper discourse

I'm not really sure why you're going through all that trouble though when the default controller_fan will do

[wary osprey]

because i did not think it through.........and you're right i'll go with the default controller fan

is it with a pwm to modulate the speed ?

[civic plover]

yes, you've got fan_speed, shutdown_speed and idle_speed

(you can't change it dynamically)