.. zephyr:board:: maker_pi_rp2040

Overview

The Cytron Maker Pi RP2040_ board is based on the RP2040 microcontroller from Raspberry Pi Ltd. The board has motor drivers, servo headers, Grove connectors and a micro USB connector.

Hardware

Microcontroller Raspberry Pi RP2040, with a max frequency of 133 MHz
Dual ARM Cortex M0+ cores
264 kByte SRAM
2 Mbyte QSPI flash
17 GPIO pins
3 ADC pins
Supply voltage measurement
I2C
UART
Micro USB connector
LiPo charger
Reset, boot and 2 user buttons
2 RGB LEDs (Neopixels)
Piezo buzzer with mute switch
4 servo ports
2 Motor drivers, with 4 manual test buttons
7 Grove connectors, of which one can be used as a Maker/Qwiic/Stemma QT/zephyr_i2c connector
13 status indicators for digital pins

Default Zephyr Peripheral Mapping

Servo header:

+-------+--------+-----------------+-----------------+ | Label | Pin | Default pin mux | Zephyr PWM name | +=======+========+=================+=================+ | GP12 | GPIO12 | PWM6A | 12 | +-------+--------+-----------------+-----------------+ | GP13 | GPIO13 | PWM6B | 13 | +-------+--------+-----------------+-----------------+ | GP14 | GPIO14 | PWM7A | 14 | +-------+--------+-----------------+-----------------+ | GP15 | GPIO15 | PWM7B | 15 | +-------+--------+-----------------+-----------------+

Motor drivers:

+-------+--------+-----------------+-----------------+ | Label | Pin | Default pin mux | Zephyr PWM name | +=======+========+=================+=================+ | M1A | GPIO8 | PWM4A | 8 | +-------+--------+-----------------+-----------------+ | M1B | GPIO9 | PWM4B | 9 | +-------+--------+-----------------+-----------------+ | M2A | GPIO10 | PWM5A | 10 | +-------+--------+-----------------+-----------------+ | M2B | GPIO11 | PWM5B | 11 | +-------+--------+-----------------+-----------------+

Grove connector 1:

+-------+--------+-----------------+ | Label | Pin | Default pin mux | +=======+========+=================+ | GP0 | GPIO0 | UART0 TX | +-------+--------+-----------------+ | GP1 | GPIO1 | UART0 RX | +-------+--------+-----------------+

Grove connector 2:

Use an adapter cable to connect Qwiic/Stemma QT sensors (that use I2C) to this connector, which is mapped to the zephyr_i2c devicetree node label.

+-------+--------+-----------------+ | Label | Pin | Default pin mux | +=======+========+=================+ | GP2 | GPIO2 | I2C1 SDA | +-------+--------+-----------------+ | GP3 | GPIO3 | I2C1 SCL | +-------+--------+-----------------+

Grove connector 3:

+-------+--------+------------+ | Label | Pin | Notes | +=======+========+============+ | GP4 | GPIO4 | Alias led0 | +-------+--------+------------+ | GP5 | GPIO5 | Alias led1 | +-------+--------+------------+

Grove connector 4:

+-------+--------+ | Label | Pin | +=======+========+ | GP16 | GPIO16 | +-------+--------+ | GP17 | GPIO17 | +-------+--------+

Grove connector 5:

+-------+--------+-----------------+-----------------+ | Label | Pin | Default pin mux | Notes | +=======+========+=================+=================+ | GP6 | GPIO6 | | | +-------+--------+-----------------+-----------------+ | GP26 | GPIO26 | ADC0 | Also in Grove 6 | +-------+--------+-----------------+-----------------+

Grove connector 6:

+-------+--------+-----------------+-----------------+ | Label | Pin | Default pin mux | Notes | +=======+========+=================+=================+ | GP26 | GPIO26 | ADC0 | Also in Grove 5 | +-------+--------+-----------------+-----------------+ | GP27 | GPIO27 | ADC1 | | +-------+--------+-----------------+-----------------+

Grove connector 7:

+-------+--------+-----------------+ | Label | Pin | Default pin mux | +=======+========+=================+ | GP7 | GPIO7 | | +-------+--------+-----------------+ | GP28 | GPIO28 | ADC2 | +-------+--------+-----------------+

Supported Features

.. zephyr:board-supported-hw::

Programming and Debugging

.. zephyr:board-supported-runners::

By default programming is done via the USB connector. Press and hold the BOOT button, and then press the RST button, and the device will appear as a USB mass storage unit. Building your application will result in a :file:build/zephyr/zephyr.uf2 file. Drag and drop the file to the USB mass storage unit, and the board will be reprogrammed.

It is also possible to program and debug the board via the SWDIO and SWCLK pins in the DEBUG connector. You must solder a 3-pin header to the board in order to use this feature. A separate programming hardware tool is required, and for example the :command:openocd software is used. Typically the OPENOCD and OPENOCD_DEFAULT_PATH values should be set when building, and the --runner openocd argument should be used when flashing. For more details on programming RP2040-based boards, see :ref:rpi_pico_programming_and_debugging.

Flashing

To run the :zephyr:code-sample:blinky sample:

.. zephyr-app-commands:: :zephyr-app: samples/basic/blinky/ :board: maker_pi_rp2040 :goals: build flash

Try also the :zephyr:code-sample:led-strip, :zephyr:code-sample:hello_world, :zephyr:code-sample:button, :zephyr:code-sample:input-dump and :zephyr:code-sample:adc_dt samples.

The use of the Maker/Qwiic/Stemma QT I2C connector (Grove 2) is demonstrated using the :zephyr:code-sample:light_sensor_polling sample and a separate shield:

.. zephyr-app-commands:: :zephyr-app: samples/sensor/light_polling :board: maker_pi_rp2040 :shield: adafruit_veml7700 :goals: build flash

Use the shell to control the GPIO pins:

.. zephyr-app-commands:: :zephyr-app: samples/sensor/sensor_shell :board: maker_pi_rp2040 :gen-args: -DCONFIG_GPIO=y -DCONFIG_GPIO_SHELL=y :goals: build flash

To set one of the GPIO pins high, use these commands in the shell, and study the indicator LEDs:

.. code-block:: shell

gpio conf gpio0 16 o
gpio set gpio0 16 1

Servo motor control is done via PWM outputs. The :zephyr:code-sample:servo-motor sample sets servo position timing (via an overlay file) for the output GP12:

.. zephyr-app-commands:: :zephyr-app: samples/basic/servo_motor/ :board: maker_pi_rp2040 :goals: build flash

It is also possible to control servos via the pwm shell:

.. zephyr-app-commands:: :zephyr-app: samples/sensor/sensor_shell :board: maker_pi_rp2040 :gen-args: -DCONFIG_PWM=y -DCONFIG_PWM_SHELL=y :goals: build flash

Use shell commands to set the position of the servo. Most servo motors can handle pulse times between 800 and 2000 microseconds:

.. code-block:: shell

pwm usec pwm@40050000 12 20000 800
pwm usec pwm@40050000 12 20000 2000

To use the buzzer, you must turn on the buzzer switch on the short side of the board. Then build using the same command as above for the sensor_shell. Use these shell commands to turn on and off the buzzer:

.. code-block:: shell

pwm usec pwm@40050000 6 1000 500
pwm usec pwm@40050000 6 1000 0

You can also control the motor outputs via the shell. To set the speed of motor 1 to 100%, 50%, 20% and 0% respectively, use these commands:

.. code-block:: shell

pwm usec pwm@40050000 8 1000 1000 pwm usec pwm@40050000 8 1000 500 pwm usec pwm@40050000 8 1000 200 pwm usec pwm@40050000 8 1000 0

To run the motor in the opposite direction at 80%:

.. code-block:: shell

pwm usec pwm@40050000 9 1000 800

The sensor_shell sample is used also to measure the supply voltage. This is the result when running on a Vin voltage slightly less than 6 Volt:

.. code-block:: shell

sensor get vbatt channel type=33(voltage) index=0 shift=3 num_samples=1 value=32688380776ns (5.977999)

References

.. target-notes::

.. _Cytron Maker Pi RP2040: https://www.cytron.io/p-maker-pi-rp2040-simplifying-robotics-with-raspberry-pi-rp2040

.. _schematic: https://drive.google.com/file/d/1BNqbxXScMXnL3-2YYfbR66nFCD1li71X/view