Are Serial 2 Pins on Photon 5v Tolerant?

@rickkas7 or anybody on here know if the Serial 2 RX pins are 5v tolerant or not?

I need to try the RX on Serial2 port since I’m seeing issues using Serial1 + Softserial at the same time.

Yes, they are 5V tolerant.

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Thanks for the quick response :particle:

Are the Serial 1 TX and RX lines also 5v Tolerant I assume so but want to confirm since I didn’t see the TX/RX pins listed in the Photon Datasheet unless they are throw in the Digital I/O line up which would mean they are 5v tolerant.

The RX and TX pins (Serial1) are 5V tolerant. They’re not a 5V TTL serial port since the TX pin only provides 3.3V, but assuming the other side tolerates 3.3V for high level (most do), then you’ll be fine.

Good to know.

For this project I’m using the RX ports for receiving data and not using the TX ports to send data.

I only removed the BLUE LED / Serial2 RX resistor since I’m needing to read the RX line but I wanted to ask if I should also remove the Green LED/ Serial2 TX resistor also if I’m not using that port for this project.

I’m guessing I’ll still get some LED light patterns with Green & RED vs. just removing them all.

Was wondering what your advice is as far as removing the resistors.

Since you are only using RX, you only need to remove the one resistor.

If you use both RX and TX you need to remove the two resistors. I removed all three because with only one LED working the color patterns are useless.

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