pico-examples

Raspberry Pi Pico SDK Examples

Getting started

See Getting started with Raspberry Pi Pico-series and the README in the pico-sdk for information on getting up and running.

Notes on different boards and platforms (RP2040 / RP2350)

The majority of examples are applicable to both RP2040 and RP2350 based boards, however certain examples that use chip-specific functionality will only build on that platform. Similarly, Wi-Fi and Bluetooth examples will only build on a board that includes Wi-Fi and Bluetooth support.

Platform and board information are passed to the CMake build via the PICO_PLATFORM and PICO_BOARD variables.

By default, the Pico SDK targets builds for RP2040 (PICO_PLATFORM=rp2040). To build for RP2350 instead, pass -DPICO_PLATFORM=rp2350 to CMake (or -DPICO_PLATFORM=rp2350-riscv for RISC-V). Alternatively, in many cases, you can rely on the board configuration to set the platform for you. For example, passing -DPICO_BOARD=pico2 will automatically select PICO_PLATFORM=rp2350.

For more information see the "Platform and Board Configuration" chapter of the Raspberry Pi Pico-series C/C++ SDK book.

Information on which examples are not being built is displayed during the CMake configuration step.

First Examples

App	Description	Link to prebuilt UF2
hello_serial	The obligatory Hello World program for Pico (output over serial version).
hello_usb	The obligatory Hello World program for Pico (output over USB version).	https://rptl.io/pico-hello-usb
blink	Blink a LED on and off. Works on both boards with regular LEDs and boards like Pico W where the LED is connected via the Wi-Fi chip.	https://rptl.io/pico-blink
blink_simple	Blink a LED on and off. Does not work on boards like Pico W where the LED is connected via the Wi-Fi chip.
picow_blink	Blinks the on-board LED on boards like Pico W where the LED is connected via the Wi-Fi chip.	http://rptl.io/pico-w-blink

ADC

App	Description
hello_adc	Display the voltage from an ADC input.
joystick_display	Display a Joystick X/Y input based on two ADC inputs.
adc_console	An interactive shell for playing with the ADC. Includes example of free-running capture mode.
onboard_temperature	Display the value of the onboard temperature sensor.
microphone_adc	Read analog values from a microphone and plot the measured sound amplitude.
dma_capture	Use the DMA to capture many samples from the ADC.
read_vsys	Demonstrates how to read VSYS to get the voltage of the power supply.

async_context

App	Description
simple_at_time_worker	Use a worker on a threadsafe background context to blink the on-board LED.

Binary Info

App	Description
blink_any	Uses bi_ptr variables to create a configurable blink binary - see the separate README for more details.
hello_anything	Uses bi_ptr variables to create a configurable hello_world binary - see the separate README for more details.

Bootloaders (RP235x Only)

These examples all produce multiple UF2s - a bootloader UF2, and then a separate UF2 of the program that the bootloader will load and boot. To load them onto a device with empty flash, first load the bootloader UF2, then reset to BOOTSEL mode and load the program UF2. This ordering is required because the bootloaders contain embedded partition tables - see section 5.10.6 in the RP2350 datasheet for more details on those.

App	Description
enc_bootloader	A bootloader which decrypts binaries from flash into SRAM. See the separate README for more information.
uart_boot	A bootloader which boots a separate RP2350 using the UART boot interface. See section 5.8 in the datasheet for more details, including the wiring requirements.

Clocks

App	Description
hello_48MHz	Change the system clock frequency to 48 MHz while running.
hello_gpout	Use the general purpose clock outputs (GPOUT) to drive divisions of internal clocks onto GPIO outputs.
hello_resus	Enable the clock resuscitate feature, "accidentally" stop the system clock, and show how we recover.
detached_clk_peri	Detach peripheral clock and vary system clock.

CMake

App	Description
build_variants	Builds two versions of the same app with different configurations.

DCP (RP235x Only)

App	Description
hello_dcp	Use the double-precision coprocessor directly in assembler.

DMA

App	Description
hello_dma	Use the DMA to copy data in memory.
control_blocks	Build a control block list, to program a longer sequence of DMA transfers to the UART.
channel_irq	Use an IRQ handler to reconfigure a DMA channel, in order to continuously drive data through a PIO state machine.
sniff_crc	Use the DMA engine's 'sniff' capability to calculate a CRC32 on a data buffer.

Encrypted (RP235x Only)

App	Description
hello_encrypted	Create a self-decrypting binary, using the hardened decryption stage. This should be secure against side channel attacks.
hello_encrypted_mbedtls	Create a self-decrypting binary, using the MbedTLS decryption stage. This is not secure against side channel attacks, so is fast but provides limited protection.

HSTX (RP235x Only)

App	Description
dvi_out_hstx_encoder	Use the HSTX to output a DVI signal with 3:3:2 RGB.

Flash

App	Description
cache_perfctr	Read and clear the cache performance counters. Show how they are affected by different types of flash reads.
nuke	Obliterate the contents of flash. An example of a NO_FLASH binary (UF2 loaded directly into SRAM and runs in-place there). A useful utility to drag and drop onto your Pico if the need arises.
program	Erase a flash sector, program one flash page, and read back the data.
xip_stream	Stream data using the XIP stream hardware, which allows data to be DMA'd in the background whilst executing code from flash.
ssi_dma	DMA directly from the flash interface (continuous SCK clocking) for maximum bulk read performance.
runtime_flash_permissions	Demonstrates adding partitions at runtime to change the flash permissions.
partition_info	Extract and enumerate partition information (address ranges, permissions, IDs, and names) from the partition table.

FreeRTOS

These examples require you to set the FREERTOS_KERNEL_PATH to point to the FreeRTOS Kernel. See https://github.com/FreeRTOS/FreeRTOS-Kernel

App	Description
hello_freertos_one_core	Demonstrates how to run FreeRTOS and tasks on one core.
hello_freertos_two_cores	Demonstrates how to run FreeRTOS and tasks on two cores.
hello_freertos_static_allocation	Demonstrates how to run FreeRTOS on two cores with static RAM allocation.

GPIO

App	Description
hello_7segment	Use the GPIOs to drive a seven segment LED display.
hello_gpio_irq	Register an interrupt handler to run when a GPIO is toggled.
dht_sensor	Use GPIO to bitbang the serial protocol for a DHT temperature/humidity sensor.

See also: blink, blinking an LED attached to a GPIO.

HW divider

App	Description
hello_divider	Show how to directly access the hardware integer dividers, in case AEABI injection is disabled.

I2C

App	Description
bus_scan	Scan the I2C bus for devices and display results.
bmp280_i2c	Read and convert temperature and pressure data from a BMP280 sensor, attached to an I2C bus.
ina219_i2c	Monitor power usage of another Pico device using an ina219 sensor, via I2C.
ina228_i2c	Monitor power usage of another Pico device ina228 sensor, via I2C.
ina237_i2c	Monitor power usage of another Pico device using an ina237 sensor, via I2C.
ina260_i2c	Monitor power usage of another Pico device using an ina260 sensor, via I2C.
lcd_1602_i2c	Display some text on a generic 16x2 character LCD display, via I2C.
lis3dh_i2c	Read acceleration and temperature value from a LIS3DH sensor via I2C
mcp9808_i2c	Read temperature from a MCP9808 sensor, set limits and raise alerts when limits are surpassed.
mma8451_i2c	Read acceleration from a MMA8451 accelerometer and set range and precision for the data.
mpl3115a2_i2c	Interface with an MPL3115A2 altimeter, exploring interrupts and advanced board features, via I2C.
mpu6050_i2c	Read acceleration and angular rate values from a MPU6050 accelerometer/gyro, attached to an I2C bus.
ssd1306_i2c	Convert and display a bitmap on a 128x32 or 128x64 SSD1306-driven OLED display.
pa1010d_i2c	Read GPS location data, parse and display data via I2C.
pcf8523_i2c	Read time and date values from a PCF8523 real time clock. Set current time and alarms on it.
ht16k33_i2c	Drive a 4 digit 14 segment LED with an HT16K33.
slave_mem_i2c	i2c slave example where the slave implements a 256 byte memory.
slave_mem_i2c_burst	i2c slave example where the slave implements a 256 byte memory. This version inefficiently writes each byte in a separate call to demonstrate read and write burst mode.

Interpolator

App	Description
hello_interp	A bundle of small examples, showing how to access the core-local interpolator hardware, and use most of its features.

Low Power

These examples demonstrate how to use the pico_low_power library.

App	Description
low_power_domant_timer	Go dormant (disable clocks) and wakeup on a timer. Requires an external clock for when testing with RP2040. See low_power_clksrc.
low_power_dormant_gpio	Go dormant (disable clocks) and wakeup on a GPIO.
low_power_pstate_timer	Go to a lower power state (RP2350 only) and restart on an AON timer.
low_power_pstate_gpio	Go to a lower power state (RP2350 only) and restart on a GPIO.
low_power_sleep_timer	Go to sleep and wakeup on a timer.
low_power_sleep_gpio	Go to sleep and wakeup on a GPIO.

Multicore

App	Description
hello_multicore	Launch a function on the second core, printf some messages on each core, and pass data back and forth through the mailbox FIFOs.
multicore_fifo_irqs	On each core, register an interrupt handler for the mailbox FIFOs. Show how the interrupt fires when that core receives a message.
multicore_runner	Set up the second core to accept, and run, any function p