Pico SCPI Lab Switch: automate your test setup with a standards compliant multi-channel switch – Forum – Raspberry Pi

Automated test setups often need switches:

  • to turn signals on and off
  • to enable or disable supplies
  • to add or remove output loads
  • to connect a measurement instrument to several circuit nodes and collect data
  • that integrate seamlessly with LabVIEW and pyvisa test setups

LabVIEW compatible. This video shows the WIP VI Virtual Instrument driver

In this blog series, I develop a lab switch that can do that. Programmable via SCPI. Plug-and-play compatible with the VISA test & measurement device standards. It supports the USBTMC standard and is IEEE 488.2 compliant. It can control any 3.3V compatible relay/switch circuit.


The core is a Raspberry Pico. Firmware is 97% based on SCPI and USBTMC cross-platform libraries. 3% (less than 30 lines of source code) is Pico specific.


The number of switches you can control is only limited by the amount of available GPIOs on the PICO.

image: WIP VI Virtual Instrument driver example

  • all standard SCPI commands (*IDN?, *RST, SYST:ERR…)
  • control a switch: DIGI:OUTP# 0|1
  • poll a switch state: DIGI:OUTP#?

The firmware is SCPI and IEEE488.2 compliant.
Free to use – also for commercial applications. No restrictions and no promises. Please respect the licenses of the 3rd party libraries that are used in the project.
Check the last post for source code and Pico ready-to-load binary firmware.

link to all posts

Read more here: Source link