Configure a Fake Board

The fake board returns incrementing values for digital interrupt ticks and analogs.

Configure a fake board to test integrating a board into your machine without physical hardware:

{
  "components": [
    {
      "name": "<your-fake-board-name>",
      "model": "fake",
      "type": "board",
      "namespace": "rdk",
      "attributes": {
        "fail_new": <boolean>
      },
      "depends_on": []
    }
  ]
}

The following attributes are available for fake boards:

Attribute configuration

Configuring these attributes on your board allows you to integrate analog-to-digital converters and digital interrupts into your machine.

analogs

An analog-to-digital converter (ADC) takes a continuous voltage input (analog signal) and converts it to an discrete integer output (digital signal).

ADCs are useful when building a robot, as they enable your board to read the analog signal output by most types of sensors and other hardware components.

To integrate an ADC into your machine, you must first physically connect the pins on your ADC to your board.

Then, integrate analogs into the attributes of your board by following the Config Builder instructions or by adding the following to your board’s JSON configuration:

// "attributes": { ... ,
"analogs": [
  {
    "name": "<your-analog-reader-name>",
    "pin": "<pin-number-on-adc>",
    "spi_bus": "<your-spi-bus-index>",
    "chip_select": "<chip-select-index>",
    "average_over_ms": <int>,
    "samples_per_sec": <int>
  }
]

{
  "components": [
    {
      "model": "pi",
      "name": "your-board",
      "type": "board",
      "attributes": {
        "analogs": [
          {
            "name": "current",
            "pin": "1",
            "spi_bus": "1",
            "chip_select": "0"
          },
          {
            "name": "pressure",
            "pin": "0",
            "spi_bus": "1",
            "chip_select": "0"
          }
        ]
      }
    }
  ]
}

The following properties are available for analogs:

Test analogs

Once you have configured your analogs, open the board’s TEST panel on the CONFIGURE or CONTROL tabs to monitor analogs. The numbers displayed next to each analog name represent the digital signal received from the analog inputs.

digital_interrupts

Interrupts are a method of signaling precise state changes. Configuring digital interrupts to monitor GPIO pins on your board is useful when your application needs to know precisely when there is a change in GPIO value between high and low.

• When an interrupt configured on your board processes a change in the state of the GPIO pin it is configured to monitor, it ticks to record the state change. You can stream these ticks with the board API’s StreamTicks(), or get the current value of the digital interrupt with Value().
• Calling GetGPIO() on a GPIO pin, which you can do without configuring interrupts, is useful when you want to know a pin’s value at specific points in your program, but is less precise and convenient than using an interrupt.

Integrate digital_interrupts into your machine in the attributes of your board by following the Config Builder instructions, or by adding the following to your board’s JSON configuration:

// "attributes": { ... ,
"digital_interrupts": [
  {
    "name": "<your-digital-interrupt-name>",
    "pin": "<pin-number>"
  }
]

{
  "components": [
    {
      "model": "pi",
      "name": "your-board",
      "type": "board",
      "attributes": {
        "digital_interrupts": [
          {
            "name": "your-interrupt-1",
            "pin": "15"
          },
          {
            "name": "your-interrupt-2",
            "pin": "16"
          }
        ]
      }
    }
  ]
}

The following properties are available for digital_interrupts:

Test digital_interrupts

Once you have configured your digital interrupts, open the board’s TEST panel on the CONFIGURE or CONTROL tabs to monitor interrupt activity. The value displayed next to each interrupt name represents the total count of interrupts triggered by the corresponding digital interrupt.

Troubleshooting

If your board is not working as expected, follow these steps:

1. Check your machine logs on the LOGS tab to check for errors.
2. Review this board model’s documentation to ensure you have configured all required attributes.
3. Check that all wires are securely connected.
4. Click on the TEST panel on the CONFIGURE or CONTROL tab and test if you can use the board there.

If none of these steps work, reach out to us on the Community Discord and we will be happy to help.

Next steps

For more configuration and usage info, see: