Pico Relay B

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Pico RTC DS3231
Pico RTC DS3231




Primary Attribute
Category: OLEDs / LCDs, LCD
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Brand: Waveshare
International: Waveshare website
Chinese: 官方中文站点
Onboard Interfaces
Related Products


Industrial 8-Channel Relay Module For Raspberry Pi Pico, Power Supply Isolation, Photocoupler Isolation


  • Onboard unibody power supply isolation, provides stable isolated voltage, needs no extra power supply for the isolated terminal
  • Onboard photocoupler isolation, prevent interference from external high-voltage circuit connected to the relay
  • High-quality relay, contact rating: 10A 250V AC or ≤10A 30V DC
  • ABS protection enclosure with rail-mount support, easy to install, safe to use
  • Breakout USB port and BOOT pin, make it easy to debug without disassembling the enclosure
  • PWR indicator, RGB LED, and passive buzzer outside the enclosure


  • Operating voltage: 5V
  • Communication Protocol: USB
  • Communication interface: Micro USB
  • Relay channel: 8 ch
  • Contact form: 1NO 1NC



Hardware connection

Relay B Pico Description
VCC VSYS Power input
GND GND Ground
CH1 GP21 Control pin of Channel 1
CH2 GP20 Control pin of Channel 2
CH3 GP19 Control pin of Channel 3
CH4 GP18 Control pin of Channel 4
CH5 GP17 Control pin of Channel 5
CH6 GP16 Control pin of Channel 6
CH7 GP15 Control pin of Channel7
CH8 GP14 Control pin of Channel 8
RGB GP13 Control pin of RGB LED
BUZZER GP6 Control pin of buzzer



Setup environment

Please refer to Raspberry Pi's guide: https://www.raspberrypi.org/documentation/pico/getting-started/

Raspberry Pi

1. Open a terminal of Raspberry Pi
2. Download and unzip the demo codes to directory Pico C/C++ SDK

sudo apt-get install p7zip-full
cd ~
sudo wget  https://www.waveshare.net/w/upload/a/a1/Pico-Relay-B_code.7z
7z x Pico-Relay-B_code.7z -o./Pico-Relay-B_code
cd ~/Pico-Relay-B_code
cd c/build/p


1. Hold the BOOTSEL button of Pico, and connect the USB interface of Pico to Raspberry Pi then release the button.
2. Go into the build directory and add the SDK path.

cd ~/Pico-Relay-B_code/c/
cd build
export PICO_SDK_PATH=../../pico-sdk

3. Run the command cmake to generate the Makefile file

cmake ..

4. Run the command make to build and generate the executable file.

make -j9

4. after building, a uf2 file is generated. Press and hold the button of the Pico board, connect it to Raspberry Pi by USB cable and then release the button. Copy the main.uf2 file generated to the recognized movable disk (RPI-RP2).

cp main.uf2 /media/pi/RPI-RP2/


1. Refer to Raspberry Pi's guides to setup Micropython firmware for Pico
2. Open the Thonny IDE, and drag the demo to IDE and run on Pico as below.
3. Choose File -> Open -> Pico-Relay-B_test.py file and run it


  • Download and unzip the demo to your Windows desktop, refer to Raspberry Pi's guides to set up the Windows software environment settings.
  • Press and hold the BOOTSEL button of Pico, connect the USB of Pico to the PC with a MicroUSB cable. Import c or python program into Pico to make it run.


Demo codes


If you require technical support, please go to the Support page and open a tickets.