Hello, I have a non-5V tolerant wireless module (RFM69HW). I'm using it on a ultrasonic distance transmitter that runs on 5V. The I/O for the ultrasonic distance module (trigger, echo) is also 5V. The wireless module is on a 3.3V regulator, and the Arduino I/O itself is on 3.3V I/O, so I'm not hur…

5V ultrasonic device on Arduino, might've broken non-5V tolerant wireless module

Grumpy_Mike May 11, 2014, 8:41am 2

and the Arduino I/O itself is on 3.3V I/O

This has me puzzled can you explain more?