pca module

This pca module implements an Adafruit PCA9685 I²C Interface using the rdk:component:board API.

Note

Before configuring your board, you must create a machine.

Navigate to the CONFIGURE tab of your machine in the Viam app. Add board / pca:pca9685 to your machine.

Usage

To use this board, connect servo(s) to one of the 16 outputs on the board. Then configure them in Viam as a GPIO Servo with the board set to the configured pca9685 board and pin corresponding to the slot it is plugged into (0-15).

For example, if you have a configured pca9685 board called "servo-board" and a servo plugged into the first output, you'd configure a gpio servo like this:

{
  "name": "servo-1",
  "api": "rdk:component:servo",
  "model": "rdk:builtin:gpio",
  "attributes": {
    "pin": "0",
    "board": "servo-board",
  }
}

Configure your pca9685 board

Copy and paste the following attribute template into your board's attributes field:

{
  "i2c_bus": "<your-i2c-bus-index>",
  "i2c_address": <int>
}

Attributes

The following attributes are available for viam:pca:pca9685 boards:

Attribute	Type	Required?	Description
i2c_bus	string	Required	The index of the I2C bus on the board with GPIO pins your pca9685 is connected to. Often a number. Example: ”1”
i2c_address	int	Optional	The PCA9685's unique [I2C address] in decimal. Default: 68 (0x40)

Example configuration

viam:pca:pca9685

  {
      "name": "<your-pca-pca9685-board-name>",
      "model": "viam:pca:pca9685",
      "type": "board",
      "namespace": "rdk",
      "attributes": {
        "i2c_bus": "1",
        "i2c_address": 68
      },
      "depends_on": []
  }

Next Steps

• Add and configure one or more GPIO Servos.
• To test your board, expand the TEST section of its configuration pane or go to the CONTROL tab.
• To write code against your board, use one of the available SDKs.
• To view examples using a board component, explore these tutorials.