Skip to content

Latest commit

 

History

History
199 lines (154 loc) · 7.21 KB

esp32.md

File metadata and controls

199 lines (154 loc) · 7.21 KB
title linkTitle weight type description images imageAlt tags aliases micrordk_component
Configure an ESP32 Board (viam-micro-server)
esp32
20
docs
Configure an ESP32 board running viam-micro-server.
/installation/thumbnails/esp32-espressif.png
E S P 32 - espressif
board
components
/micro-rdk/board/esp32/
/build/micro-rdk/board/esp32/
/components/board/esp32/
true

{{% alert title="REQUIREMENTS" color="caution" %}}

Follow the setup guide to install and run viam-micro-server before configuring an esp32 board.

Viam recommends purchasing the ESP32 with a development board. The following ESP32 microcontrollers are supported:

  • ESP-32-WROVER Series

Your microcontroller should have at least the following resources available to work with viam-micro-server:

  • 2 Cores + 384kB SRAM + 2MB PSRAM + 8MB Flash

{{% /alert %}}

To test your board as you configure it, power it on. If you plan to connect hardware to the board's pins, connect the hardware while it's powered off. To configure an esp32 board, navigate to the CONFIGURE tab of your machine's page in the Viam app and select JSON mode.

{{< alert title="Info" color="info" >}}

Theesp32 board model is not currently available as a built-in option in the Viam app, so you cannot use Builder mode to configure this board.

{{< /alert >}}

Copy the following JSON template and paste it into your configuration inside the "components" array:

{{< tabs name="Configure an esp32 Board" >}} {{% tab name="JSON Template"%}}

{
  "name": "<your-board-name>",
  "model": "esp32",
  "api": "rdk:component:board",
  "attributes": {
    "pins": [
      <int>
    ],
    "analogs": [
      {
        "pin": <int>,
        "name": "<your-analog-name>"
      }
    ],
    "digital_interrupts" : [
        {
         "pin": <int>
        }
    ]
  },
  "depends_on": []
}

{{% /tab %}} {{% tab name="JSON Example" %}}

{
  "name": "board",
  "model": "esp32",
  "api": "rdk:component:board",
  "attributes": {
    "pins": [15, 34],
    "analogs": [
      {
        "pin": "34",
        "name": "sensor"
      }
    ],
    "digital_interrupts": [
      {
        "pin": 4
      }
    ]
  },
  "depends_on": []
}

{{% /tab %}} {{< /tabs >}}

Edit and fill in the attributes as applicable. Click the Save button in the top right corner of the page.

The following attributes are available for esp32 boards:

Name Type Required? Description
analogs array Optional Attributes of any pins that can be used as analog-to-digital converter (ADC) inputs. See configuration info.
i2cs array Optional Any Inter-Integrated Circuit (I2C) pins' bus index and name. See configuration info.
digital_interrupts array Optional Any digital interrupts' GPIO number. See configuration info.
pins array Optional The GPIO number of any GPIO pins you wish to use as input/output with the board API.

Any pin not specified in either "pins" or "digital_interrupts" cannot be interacted with through the board API. Interaction with digital interrupts is only supported with the board API; these digital interrupts cannot be used as software interrupts in driver implementations.

analogs

The following properties are available for analogs:

Name Type Required? Description
name string Required Your name for the analog reader.
pin integer Required The GPIO number of the ADC's connection pin, wired to the board.

i2cs

The following properties are available for i2cs:

Name Type Required? Description
name string Required name of the I2C bus.
bus string Required The index of the I2C bus. Must be either i2c0 or i2c1.
data_pin integer Optional The GPIO number of the data pin. Default: 11.
clock_pin integer Optional The GPIO number of the clock pin. Default: 6.
baudrate_hz integer Optional The baudrate in HZ of this I2C bus.
Default: 1000000
timeout_ns integer Optional Timeout period for this I2C bus in nanoseconds.
Default: 0

digital_interrupts

The following properties are available for digital_interrupts:

Name Type Required? Description
pin integer Required The GPIO number of the board's GPIO pin that you wish to configure the digital interrupt for.

PWM signals on esp32 pins

You can set PWM frequencies with Viam through the GPIOPin API. Refer to the Espressif documentation for valid frequencies and duty resolutions. A configured esp32 board can support a maximum of four different PWM frequencies simultaneously, as the boards only have four available timers.

For example:

Pin PWM Frequency (Hz)
12 2000
25 3000
26 5000
32 6000

At this point, if you want to add another PWM signal, you must do the following:

  1. Set the PWM frequency before the duty cycle.
  2. Set the PWM frequency to one of the above previously set frequencies.

For example, you can set pin 33 to 2000 Hz:

Pin PWM Frequency (Hz)
12, 33 2000
25 3000
26 5000
32 6000

Then, follow these requirements to change the PWM frequencies of a pin:

  1. If no other pins have a signal of the same frequency (for example, pins 25, 26, and 32), you can freely change their PWM frequency.
  2. If one or more pins are sharing the old frequency (for example, pins 12 and 33):
    1. If there are less than 4 active frequencies, you can change the PWM frequency freely because there will be a timer available.
    2. If there are already 4 active frequencies, changing the PWM frequency of the pin will raise an error because there are no timers available. Free a timer by setting the PWM frequencies of all of the pins to 0.

Troubleshooting

{{< readfile "/static/include/components/troubleshoot/board.md" >}}

Next steps

For more configuration and usage info, see:

{{< cards >}} {{% card link="/dev/reference/apis/components/board/" customTitle="Board API" noimage="true" %}} {{% card link="/operate/control/web-app/" noimage="true" %}} {{% card link="/tutorials/get-started/blink-an-led/" noimage="true" %}} {{< /cards >}}