Opps, forgot about 3.3V on RFM69HW

[labusr]

I forgot that RFM69's are not 5V tolerant on the I/O pins.  I supplied the VCC at 3.3V, but the Arduino is 5V I/O.  Dumb mistake.

If I made my own bread board Arduino and use 3.3V for the power supply for the Arduino itself, then my I/O pins would be at 3.3V right?  Then I can use the RFM69 directly connected to the bread board Arduino?

Otherwise if I want to keep using an Arduino, I need a "level shifter"?  When I look around to see what I need to do, I run into active low and active high level shifters.  Some people also suggested using a voltage divider, but I don't think a voltage divider will work since I need bidirectional data?  Pretty confused.  Maybe someone could simplify the electronics for me and recommend a method or module?

Thanks. 

[Felix]

A little reading in the forum will reveal tons of threads on this topic. All you need is a voltage divider using resistors (10K + 4.7K work well) INTO > RFM69 only. The other way into Arduino it doesn't matter since the Arduino will sense 3.3V levels as logic 1 so you're good there.
Powering from a regular Arduino might not be sufficient because the little 3.3V regulator on the Arduinos might not supply the 120mA needed by RFM69HW, probably enough for RFM69W though. But you can try.