Philter:
Thank you for the very fast response.
Im not realy good in english, but i try my bestOk, lets just remove the second arduino here.
We have an arduino wich should switch off the 3 communication pins whenever i want to. So another device can talk to the matrix. The easiest way i know how it will work is a relay. But i need an eletronic switch to do the job.
I want to use the LedControl.h library for the matrix. I coudnt find a comand in the library that fits my need, so i want to do it on the hardware side.
Phil
But why? This isn't how displays are driven. The display is driven by some controller, and whatever wants
to talk to the display talks to the controller, not to the display - its a black box effectively.