What's the best way to communicate between a Teensy 4.1 and an Arduino Leonardo?

[drjio]

Just picked up two 4.1's, super excited to get the speed result. I need to control an external Arduino Leonardo. I was thinking about using some sort of digital I/O via analog or digital outputs but was reading about the different interfaces. I need send about 20 or so commands over to the Arduino Leonardo for some actions.

What's the most effective and reliable way to do this without using a lot of pins? Serial? SPI? I2C?

Thanks!

 

[Gremlin]

I would say that Serial is the simplest/easiest approach.
I have seen several recommendations for using the EasyTransfer library but have not used it myself.

Here is a similar question/answer.
https://forum.pjrc.com/threads/70077-How-to-send-from-esp32-to-teensy?highlight=serial+library+communicate

 

[drjio]

Thanks, I'll dig in!

 

[MatrixRat]

Perhaps look at plugging the Leonardo into the T4x UsbHost port as well.

 

[KurtE]

Also remember that Leonardo probably runs at 5v, and T4.1 runs at 3.3v and the IO pin are NOT 5v tolerant. So might need some form of TTL level shifting if you connect the IO pins of one
to the other.

Could as mention plug it into USBHost of T4.1 and talk that way.

Sort of depends on things like how much speed, and IO do you need.

 

[drjio]

Thanks all. I didn't realize that the T4.1 runs at 3.3v, so thanks for the reminder. I'm already using the Leonardo's USB capabilities, so serial communication it is.

Thanks for the ideas!