Sensirion Raspberry Pi UART SVM40 Driver

This document explains how to set up the SEK-SVM40 evaluation kit to run on a Raspberry Pi using the provided code.

Setup Guide

Connecting the Sensor

Plug the provided USB cable into your Raspberry Pi.

If you don't have a suitable cable at hand, please find the SEK-SVM40 pinout listed below, or in the technical documentation:

Pin	Cable Color	Name	Description	Comments
1	Red	VDD	Supply Voltage	3.3 or 5.0 V
2	Black	Ground
3	Green	RX	UART: Receiving pin for communication
		SDA	I2C: Serial data, bidirectional
4	Yellow	TX	UART: Transmission pin for communication
		SCL	I2C: Serial clock
5	Blue	SEL	Interface select	Leave floating or pull to VDD to select UART
				Pull to GND to select I2C
6	Purple	NC	Do not connect

Raspberry Pi

• Install the Raspberry Pi OS on to your Raspberry Pi

• Download the driver from the Sensirion GitHub Page and extract the .zip on your Raspberry Pi

• Compile the driver

  1. Open a terminal

  2. Navigate to the driver directory. E.g. cd ~/raspberry-pi-uart-svm40

  3. Run the make command to compile the driver

     Output:

     rm -f svm40_uart_example_usage
     cc -Os -Wall -fstrict-aliasing -Wstrict-aliasing=1 -Wsign-conversion -fPIC -I. -o svm40_uart_example_usage svm40_uart.h svm40_uart.c sensirion_uart_hal.h sensirion_shdlc.h sensirion_shdlc.c \
      sensirion_uart_hal.c sensirion_config.h sensirion_common.h sensirion_common.c svm40_uart_example_usage.c
     

• Test your connected sensor

  • Run ./svm40_uart_example_usage in the same directory you used to compile the driver.

    Output:

    Serial number: 0FDBE89C00000237AE113220
    Product type: 00140000
    Product name: SVM40
    Firmware: 2.2 Debug: 0
    Hardware: 2.0
    Protocol: 1.0
    Temperature Offset: 0.00 °C
    Voc index: 0.0
    Humidity: 36.07 %RH
    Temperature: 25.83 °C
    Voc index: 0.0
    Humidity: 36.04 %RH
    Temperature: 25.82 °C
    Voc index: 0.0
    Humidity: 36.05 %RH
    Temperature: 25.83 °C
    ...