Hi everyone,
My issue is I don't know how to connect the 3.3v TX/RX pins of RN-XV to a 5V Arduino UNO. Can I use a regulator to make Arduino TX pin output 3.3V?
I know someone connects them directly, despite the 5V/3.3V thing, and it works, no damages to the Wifly module. But what is actually the exact correct way to do this?
Thank you very much!!
Karl
Karduino:
My issue is I don't know how to connect the 3.3v TX/RX pins of RN-XV to a 5V Arduino UNO. Can I use a regulator to make Arduino TX pin output 3.3V?
No, because it only allows you to step down the voltage. For an RF transciever you want a bi-directional solution, especially because the upper limit of 3.3V logic gets close to the cut-off point between LOW and HIGH on 5V logic.
I know someone connects them directly, despite the 5V/3.3V thing, and it works, no damages to the Wifly module. But what is actually the exact correct way to do this?
What you need is a bi-directional level shifter/logic converter circuit. Here's a fairly inexpensive but complete one from Sparkfun, but I'm sure you can find something similar closer to home.
If you have 4 female to male jumper wires, you can connect the RN-XV to arduino without a shield or adapter. See link below.
The UNO should have a 3.3v output pin on it. Use that. I wouldn't advise you to use the 5v.
The other pins are GND, Tx and Rx.
Basically, all these pins are Male connnector to arduino, female to RN XV.
Let us know if this works for you.
Far-seeker:
No, because it only allows you to step down the voltage. For an RF transciever you want a bi-directional solution, especially because the upper limit of 3.3V logic gets close to the cut-off point between LOW and HIGH on 5V logic.......
What you need is a bi-directional level shifter/logic converter circuit. Here's a fairly inexpensive but complete one from Sparkfun, but I'm sure you can find something similar closer to home.
Thank you very much Far seeker!! That's really helpful!! I'm going to find a converter.
Karl
jabbrwokky:
If you have 4 female to male jumper wires, you can connect the RN-XV to arduino without a shield or adapter. See link below.
The UNO should have a 3.3v output pin on it. Use that. I wouldn't advise you to use the 5v.
The other pins are GND, Tx and Rx.
Basically, all these pins are Male connnector to arduino, female to RN XV.
Let us know if this works for you.
Thank you very much for your help jabbrwokky !!
Karduino:
Thank you very much Far seeker!! That's really helpful!! I'm going to find a converter.Karl
You're quite welcome, good luck with your project.