How to fix max7219 32x8 led matrix strange behavior?

I have 32x8 led matrix (ordinary cheap Chinese module) and high power servo motor driver in the same enclosure. This driver produce a lot of EMI. Servo and arduino with matrix has different power source. I use high quality 5v 15w power supply only for arduino and led matrix. As soon as I enable servo driver, led matrix goes crazy. I almost fixed that issue by using shielded cable with ferrite bead near the display, the cable itself is around 40cm.

But problem is still here, but instead of instant strange behavior, now it happens relatively rare (after few minutes or half an hour).

Example of strange behavior:

  1. Some blocks have different brightness.
  2. Some blocks just stops working.
    This effects only disappears after restart.

I think now it can be solved through software by resetting to default each register of the matrix each few seconds.

I'm using MD_Parola library to control my matrix, which uses MD_MAX72XX.

How to solve my problem. What is the easiest way?


You have failed to specify what sort of Arduino or other board you are using, and failed to cite the full description (Web reference) to the "high power servo motor driver".

No schematic provided, Read the instructions for posting!

Arduino Mega, matrix connected to default arduino mega SPI, select pin is 53. Servo motor system - industrial 2kw chinese servo motor without brand. It even happens when driver is not connected to arduino, but close to led matrix.


  • real pictures of your setup, where we can see EACH wire and each module

Which means perfectly focused, at least 2 Megapixels but preferably four or more, and taken outside in full daylight (but not sun), not in a dimly lit room.