Take a look at this topic on the Domoticz forum: http://www.domoticz.com/forum/viewtopic.php?f=34&t=8751

Also the stock bootloader is broken so that in reboot, it sets the watchdog timer to a very small value (so that a reboot would happen before the sketch has done 'setup()'), but does not turn off the watchdog it it was enabled in the sketch -> eternal reset loop if you ever reboot from a watchdog-enabled sketch.

Optiboot, MYSBootLoader etc. would work fine.

For whatever strange reason, the Arduino stock bootloader is broken, so that it will not disable the watchdog on startup, causing just an infinite reset loop. I'd recommend updating the bootloader with something like MYSBootloader or Optiboot.

This is what I have done as a hobby so far: https://www.openhardware.io/view/41/Heatpump-airconditioner-controller

There's no Gree support in the HeatpumpIR library, though.

@dpressle said:

@ToniA can you elaborate?

Yes, on my AC IR decoder sketch I have decoder modules for different heatpumps. Like this:

https://github.com/ToniA/Raw-IR-decoder-for-Arduino/blob/master/MitsubishiElectric.cpp

So, write a new one, and add a call to it into https://github.com/ToniA/Raw-IR-decoder-for-Arduino/blob/master/rawirdecode.ino#L315. First you need to write a condition to recognize the protocol (like, from the first bytes + length etc). Then just start adding functionality, like decoding the temperature, then operating mode etc.

How about writing a new decode module into Raw-IR-decoder-for-Arduino? I find it very useful in trying to figure out how a certain A/C protocol works.

Would these help:

https://github.com/ToniA/arduino-heatpumpir
https://github.com/ToniA/Raw-IR-decoder-for-Arduino

The experience I have is from running the serial gateway on Sensebender (which is a 8MHz device, running on 3.3V). It just didn't work at all, and as soon as changed the serial speed to 38400 everything was just fine.

http://wormfood.net/avrbaudcalc.php?bitrate=300%2C600%2C1200%2C2400%2C4800%2C9600%2C14.4k%2C19.2k%2C28.8k%2C38.4k%2C57.6k%2C76.8k%2C115.2k%2C230.4k%2C250k%2C.5m%2C1m&clock=8&databits=8

It also doesn't matter whether you connect through USB or RS-232, it's still the same problem. Another 'nice' finding was that Arduino Nano has a hardware problem, it's not discovered as a USB device when Raspberry boots up. I had really interesting times when trying to use it as the serial gateway, works fine when plugged in when Raspberry is running, but it's lost on every boot.

https://ketturi.kapsi.fi/2014/04/how-to-fix-moody-arduino-nano/

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.

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.