Raspberry Pi Pico 2

The Raspberry Pi Pico 2 is a general purpose board supplied by the Raspberry Pi Foundation.

../../../../../_images/pico-2.png

Features

  • RP2350 microcontroller chip

  • Dual-core ARM Cortex M33 processor, flexible clock running up to 150 MHz

  • 520kB of SRAM, and 4MB of on-board Flash memory

  • Castellated module allows soldering direct to carrier boards

  • USB 1.1 Host and Device support

  • Low-power sleep and dormant modes

  • Drag & drop programming using mass storage over USB

  • 26 multi-function GPIO pins

  • 2× SPI, 2× I2C, 2× UART, 3× 12-bit ADC, 16× controllable PWM channels

  • Accurate clock and timer on-chip

  • Temperature sensor

  • Accelerated floating point libraries on-chip

  • 12 × Programmable IO (PIO) state machines for custom peripheral support

Serial Console

By default a serial console appears on pins 1 (TX GPIO0) and pin 2 (RX GPIO1). This console runs a 115200-8N1.

The board can be configured to use the USB connection as the serial console. See the usbnsh configuration.

Buttons and LEDs

User LED controlled by GPIO25 and is configured as autoled by default.

A BOOTSEL button, which if held down when power is first applied to the board, will cause the RP2350 to boot into programming mode and appear as a storage device to the computer connected via USB. Saving a .UF2 file to this device will replace the Flash ROM contents on the RP2350.

Pin Mapping

Pads numbered anticlockwise from USB connector.

Pad

Signal

Notes

1

GPIO0

Default TX for UART0 serial console

2

GPIO1

Default RX for UART1 serial console

3

Ground

4

GPIO2

5

GPIO3

6

GPIO4

7

GPIO5

8

Ground

9

GPIO6

10

GPIO7

11

GPIO8

12

GPIO9

13

Ground

14

GPIO10

15

GPIO11

16

GPIO12

17

GPIO13

18

Ground

19

GPIO14

20

GPIO15

21

GPIO16

22

GPIO17

23

Ground

24

GPIO18

25

GPIO19

26

GPIO20

27

GPIO21

28

Ground

29

GPIO22

30

Run

31

GPIO26

ADC0

32

GPIO27

ADC1

33

AGND

Analog Ground

34

GPIO28

ADC2

35

ADC_VREF

36

3V3

Power output to peripherals

37

3V3_EN

Pull to ground to turn off.

38

Ground

39

VSYS

+5V Supply to board

40

VBUS

Connected to USB +5V

Other RP2350 Pins

GPIO23 Output - Power supply control. GPIO24 Input - High if USB port or Pad 40 supplying power. GPIO25 Output - On board LED. ADC3 Input - Analog voltage equal to one third of VSys voltage.

Separate pins for the Serial Debug Port (SDB) are available

Power Supply

The Raspberry Pi Pico 2 can be powered via the USB connector, or by supplying +5V to pin 39. The board had a diode that prevents power from pin 39 from flowing back to the USB socket, although the socket can be power via pin 30.

The Raspberry Pi Pico chip run on 3.3 volts. This is supplied by an onboard voltage regulator. This regulator can be disabled by pulling pin 37 to ground.

The regulator can run in two modes. By default the regulator runs in PFM mode which provides the best efficiency, but may be switched to PWM mode for improved ripple by outputting a one on GPIO23.

Configurations

nsh

Basic NuttShell configuration (console enabled in UART0, at 115200 bps).

README.txt

README
======

This directory contains the porting of NuttX to the Raspberry Pi Pico 2.
See https://www.raspberrypi.org/products/raspberry-pi-pico-2/ for information
about Raspberry Pi Pico 2.

NuttX supports the following RP2350 capabilities:
  - UART  (console port)
    - GPIO 0 (UART0 TX) and GPIO 1 (UART0 RX) are used for the console.
  - ADC
  - USB device
    - CDC/ACM serial device can be used for the console.
  - Flash ROM Boot
  - SRAM Boot

Installation
============

1. Configure and build NuttX

  $ git clone https://github.com/apache/nuttx.git nuttx
  $ git clone https://github.com/apache/nuttx-apps.git apps
  $ cd nuttx
  $ make distclean
  $ ./tools/configure.sh raspberrypi-pico-2:nsh
  $ make -j

4. Connect Raspberry Pi Pico 2 board to the USB port while pressing BOOTSEL.
   The board will be detected as USB Mass Storage Device.
   Then copy "nuttx.uf2" into the device.
   (Same manner as the standard Pico SDK applications installation.)

5. To access the console, GPIO 0 and 1 pins must be connected to the
   device such as a USB-serial converter.

   `usbnsh` configuration provides the console access by USB CDC/ACM serial
   device. The console is available by using a terminal software on the USB
   host.

Defconfigs
==========

- nsh
    Minimum configuration with NuttShell

- usbnsh
    USB CDC/ACM serial console with NuttShell