Servo control with pca9685 possible?

ESPHome
1

Hi,

I would like to control 2 servos with a esp32cam using the pca9685. Connection to the pca9685 works as I also control some lights with it.

The sliders in Home Assistant do not seem to generate logs in the esp32.
Where did I do wrong?

esphome

# Enable Home Assistant API
api:
  password: ""
  services:
    - service: control_servo_1
      variables:
        level: float
      then:
        - servo.write:
            id: my_servo_1
            level: !lambda 'return level / 100.0;'
    
    - service: control_servo_2
      variables:
        level: float
      then:
        - servo.write:
            id: my_servo_2
            level: !lambda 'return level / 100.0;'

i2c:
  sda: 12
  scl: 13
  scan: true
  id: bus_a


pca9685:
  id: pca9685_1
  address: 0x40
  frequency: 60 #500

output:
  - platform: pca9685 #Ch5 - servo 1
    id: 'pca_channel5'
    channel: 5
  - platform: pca9685  #Ch6 - servo 2
    id: 'pca_channel6'
    channel: 6

servo:
  - id: my_servo_1
    output: pca_channel5

  - id: my_servo_2
    output: pca_channel6

Home Assistant:
automation.yaml:

#automation:
  - alias: Write Servo Value to ESP
    trigger:
      platform: state
      entity_id: input_number.servo_control1
    action:
      # Replace livingroom with the name you gave the ESP
      - service: esphome.esp32camera_control_servo1
        data_template:
          level: '{{ trigger.to_state.state | int }}'
          
  - alias: Write Servo2 Value to ESP
    trigger:
      platform: state
      entity_id: input_number.servo_control2
    action:
      # Replace livingroom with the name you gave the ESP
      - service: esphome.esp32camera_control_servo2
        data_template:
          level: '{{ trigger.to_state.state | int }}'

configuration.yaml:

input_number:
  servo_control1:
    name: Servo Control1
    initial: 0
    min: -100
    max: 100
    step: 1
    mode: slider
    
    
  servo_control2:
    name: Servo Control2
    initial: 0
    min: -100
    max: 100
    step: 1
    mode: slider
2

Hey Kobold, did you ever get this working? it looks like I am at the same stage you were back in Jan.

3

Hi mykey,

sorry, I ran against a wall with this and sidelined it :frowning:

4

Were you creating your input_number entity in HA? I believe you are supposed to create it in the ESP device and use “number”, not “input_number.”

See the last example shown on this page:

I got it working using your code but making this change. Hopefully you can get it to work as well. Thanks!

5

Hi mofonics,

is it possible that you can post the finished code you got working?
IM finding a way to control some Servos with my ESP8266 and PCA9685.

There are many videos for android but i cant find any documentation about it with HA only directly with the ESP8266

Thank you

6

I use an esp32 and esphome to drive continuous rotation (360) MG90 servos with the PCA9685, and here is my working code. Some things to note:

  1. Since the PCA9685 is primarily intended to drive LEDs, the range is from 0 to 100, not -100 to +100. No idea if this is a bug or not.
  2. The values I found for a 360 servo are:
  • stop: around 35
  • forward: from 40 on up (e.g. 60 is about half speed)
  • reverse: from 30 down (e.g. 15 is about half speed)

Here is the esphome code for the I2C bus to the PCA9685. Note the choice of which channel to use for each servo is arbitrary (0-15).

# there are 2 I2C buses on the ESP32
i2c:
  # define an I2C bus for the PCA9685 PWM servo driver board
  - id: bus_a
    sda: GPIO23
    scl: GPIO22
    scan: True

# 16-channel(0-15) PWM driver board with I2C control
pca9685:
  id: pca9685_1
  i2c_id: bus_a
  address: 0x40
  frequency: 60 # 60Hz for servo, 500Hz for LEDs

output:
  - platform: pca9685 #Ch2 - servo 1
    id: 'pca_channel2'
    channel: 2

  - platform: pca9685 #Ch3 - servo 2
    id: 'pca_channel3'
    channel: 3

Here is the code for the template numbers for servo control:

# Define a number template to control servo 1
number:
  - platform: template
    name: Servo 1
    id: servo1
    min_value: 0
    restore_value: False
    max_value: 100
    optimistic: true
    step: 1
    set_action:
      then:
        - servo.write:
            id: my_servo1
            level: !lambda 'return x / 100.0;'
#        - display.page.show: page1

# Define a number template to control servo 2
  - platform: template
    name: Servo 2
    id: servo2
    min_value: 0
    restore_value: False
    max_value: 100
   optimistic: true
    step: 1
    set_action:
      then:
        - servo.write:
            id: my_servo2
            level: !lambda 'return x / 100.0;'
#        - display.page.show: page1

And some handy buttons to drive the servos:

# buttons for servo control presets
# note that we use number.set rather than servo.write
# so that the number slider updates on the web page and in HA

  - platform: template
    name: "servos_forward"
    icon: "mdi:rotate-right"
    on_press:
      then:
        - number.set:
            id: servo1
            value: 10
        - number.set:
            id: servo2
            value: 60

  - platform: template
    name: "servos_reverse"
    icon: "mdi:rotate-left"
    on_press:
        - number.set:
            id: servo1
            value: 60
        - number.set:
            id: servo2
            value: 10

  - platform: template
    name: "servos_stop"
    icon: "mdi:stop"
    on_press:
      then:
        - number.set:
            id: servo1
            value: 35
        - number.set:
            id: servo2
            value: 35

Regards

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