Is it possible to connect a Pro Mini directly to Raspberry Pi GPIO for Gateway?

[drock1985]

Hi,

I'm wondering if it is possible to connect a Arduino Pro Mini directly to a Raspberry Pi's GPIO pins for running a serial gateway? I am trying to avoid using the USB bus for a Gateway and a direct connection of the NRF to the Pi is not preferred just so I don't have to compile update scripts/drivers/kernel modules/etc.

Is it possible?

Thanks!

[ToniA]

I've done the same with SenseBender, so it should work with Pro as well. You only need 4 wires, GND, Vcc, RX, TX.

If it's a 3.3V model, it runs on 8 MHz, so you need to set the serial speed to 38400. At 115200 the serial speed is too much off to work reliably.

[drock1985]

@ToniA

Awesome. What port would it be? I have tried to access the /dev/ttyAMA0 but the pi user has no access. Can connect as root, but that's overkill.

[ToniA]

It's the /dev/ttyAMA0. See this: https://www.raspberrypi.org/forums/viewtopic.php?p=139945

Domoticz runs as root (which is a really bad thing IMHO), so it has no problems with this.

[drock1985]

@ToniA

Thanks for the info. I tried playing around with it last night and like you mention, unless I invoked root, I could not get the port to work. I'm trying to see if there is another way to do it. Might have to just chmod 775 /dev/ttyAMA0 on boot.

I'll try it again later tonight when i'm home. Thanks for the help.