Interfacing with 3.3V devices (input & output pins).

Wireless & IoT
1

Hello everyone!

I need to connect my arduino to a 3.3V RF device (nordic nRF2401 to be exact). I read the interfacing 3.3V tutorial but I am still confused with one of the pin’s that require input and output. The data1 pin needs to be both (on startup for configuration and then for data retrieval). If I use a diode and a pull up resistor when the data1 pin goes low on the nRF2401 the arduino pin will still stay high. How do I create a circuit so that the data1 pin can do both?

2

where did you find the interfacing 3.3V tutorial

just starting out on these nordic nRF2401 myself…

paul

3

Nordic has an app. note on using SPI with the nRF2401, which will make it easier to interface to the AVR - you can use the SPI hardware instead of bit-banging the interface. I haven’t tried it (I now use the nRF24L01), but it should work.

Leon