USB-A ATmega32u4 PPM Receiver

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1

I have a tiny USB-A ATmega32u4 leonardo clone that has been hard to find information for. I’m setting it up to receive PPM from an R/C receiver, but I’m having a tough time figuring out which pin I should be using/what the pin name is in the code. I have successfully set up the board to show up as a HID in Windows, but I have tried multiple combinations and I am still not getting signal in the serial monitor.

This is the board: Amazon.com

And this is the code: GitHub - wireless-rc-adapter/wireless-rc-adapter: 🎮 Arduino USB-Joystick adapter for RC receivers with PWM and PPM modulations up to 8 channels.

The project code defaults to Pin 4 but that isn't available on this board. I have referenced the ATmega32u4 datasheet and followed the traces to each pad to determine which pin to use, but I'm still getting nothing. It's my understanding that to use PPM you have to use an interrupt, but I am not seeing mention of that in the code.

I'm brand new to coding and this is my first arduino project so thank you for any help/guidance.

2

A quick glance at the 32U4 datasheet and the "Micro Beetle ATmega32u4 Development Board" you linked to, the only pin (that's broken out) you can use for Input capture is the SCK pin.
This is ICP3 where the code is using ICP1 on pin 4. You would need to alter the code to use timer 3 instead of timer 1 and also use pin 13 instead of pin 4.

I have altered but not tested the ppm.ino sketch to use pin 13 and ICP3. Rename the original file to ppm.old and copy the attached file in its place.

ppm.ino (2.71 KB)

3

I can't find a schematic for this board, however unfortunately it appears that it doesn't have digital pin D13 either.

4

1116×787 152 KB

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