Free GPIO pins after plugging matrix creator to raspberry pi


I’m using matrix creator as a Recording device and I’m impressed with it’s performance.
Further I want to directly access (preferably 3) GPIO pins of raspberry pi without using the GPIO pins on Matrix creator board.
Is there any possibility that I can use some free GPIO pins of raspberry or is the matrix board uses all of it?


Hi @arunajjj66,

MATRIX Creator has GPIO available to use in the external GPIO connector. You can access the external GPIO from the 3 different layers we have in our software stack:

  • MATRIX OS (Node.js): Getting Starter guide and examples here
  • MALOS: Examples using Node.js and python examples,
  • HAL : using lower C++ layer example here and the pinout .

If you really need to use the GPIO directly form the Pi here is the MATRIX Creator Datasheet . Look for the pins that says NC (Not connected ) in the Raspberry Pi Connector .

Let me know if it helps .



Thank Yoel for the generous answer.
Yes I’m already implementing GPIO using matrix hal.
In my program I have a few parallel threads sharing SPI to get data from the microphones, change LEDs and get GPIO values.
As I have removed mutexing from SPI functions, it gives some mutations in my record files. Therefore, currently i have reduced GPIO sampling frequency.
But with your answer everything is solved :slight_smile:


Let us know how it goes and share progress here!