I think that I will have some data on that by next tuesday, since that is also my #1 requirement. I will let you know!

@gohan
Ah sorry, I misunderstood.
The RFM95s VCC is factory-wired to a regulator on the moteino. It is an out of the box MCU+Radio-Unit.
See this link for clarification:
Moteino with RFM95

Sorry for the confusion.

EDIT: I just tried changing my normal 433MHz Gateway with Arduino Nano + RFM69HCW on the RPi for a Moteino-integrated-RFM69HCW one.
I have the same problem with that as with the LoRa Moteino GW... It works fine with the PC and even gets readings far away, I normally do not get.
Hooking it up to the RPi with FHEM it stops working...
I can't really explain that?

EDIT 2: I checked the debug of the sensor-sided unit. It says st=OK...
So I guess I'll have to check my hardware (FTDI etc.)

Thank you for the advice!

To begin with I followed lafleurs advice from this thread: https://forum.mysensors.org/topic/6718/8bit-or-32bit-processors/4

Unfortunately I wasn't able to establish communication by using the Zero-Board-definitions. I didn't really figure out what screwed up, since I was able to compile but it never really worked and I had no Serial-Monitor available.

Even tweaking the hardware definiton files didn't really work out. So I had a look into the initial error again to make it work with original Adafruit-FeatherM0-definitions. And I don't know why I didn't see that earlier:

Since SerialUSB wasn't declared I did a quick search for that error and I found this: https://forums.adafruit.com/viewtopic.php?f=22&t=88793

Apparently they changed "SerialUSB" to only "Serial".
I edited that in MyHwSAMD.h from

#ifndef MY_SERIALDEVICE
#define MY_SERIALDEVICE SerialUSB
#endif

to

#ifndef MY_SERIALDEVICE
#define MY_SERIALDEVICE Serial
#endif

and it seems to work now.
I will have to check with a gateway tomorrow. I hope this helps anyone in the future.

And btw. for the M0-Feather the PINs changed (I found that for the 32u4 and didn't notice the difference immediately).
You now need to define this before including the MySensors.h

    #define MY_RF69_SPI_CS 8
    #define MY_RF69_IRQ_PIN 3
    #define MY_RF69_IRQ_NUM 3

Thanks for the help and setting me on the right track! I will post if it works tomorrow.

Hi, I am also trying to get them to work and stumbled upon this. I will try that and let you know if it works.

@webzter30 I guess he connected it to RST on the Adafruit-board. He mentioned that before. And the breakout does work with 3-5V, so it should work with almost anything. But Adafruit stated that you should use the same power on VIN as on the logic circuits. So for a Nano that would be 5V

EDIT: Works for me! Thanks.

I tried both. 3.3/5V over FTDI and 5V externally.

Hey guys, a little later but still I've got "kind of" news.
Everything I tried to get the Moteino as GW to work consistently failed.
It seems the problem either lay with the FTDI or the Moteino as GW. Since I am using a Nano with an Adafruit Breakout RFM95W everything just works fine. It is a little unsatisfying but as I only need Moteinos for Nodes (low battery drain) I will go with this (cheaper) GW.

@gohan
Your point made me look something up. Even though I do use the 2.5 amps powersupply for the RPi3 Model B I did find, that the RPi can only take up to 1Amp max. and depending on what's it doing, it can consume between 700-1000 mA.
So hooking up the Moteino + FTDI may max that out even though the USB-Port should supply up to 500mA.
raspberrypi.org

Typically, the model B uses between 700-1000mA depending on what peripherals are connected; the model A can use as little as 500mA with no peripherals attached. The maximum power the Raspberry Pi can use is 1 Amp. If you need to connect a USB device that will take the power requirements above 1 Amp, then you must connect it to an externally-powered USB hub.

So I'll try an active HUB next. And if that works I might give this a try:
Boost USB-Power
This site claims that a change in the RPi's config file should boost the max output current to 1.2 A... Sounds a little wild and unhealthy but I'll give it a shot.

Also FTDIchip.com claims that you should use an external USB-power-supply when powering devices with more than 100mA. Everything points into one direction

@gohan
Ah sorry, I misunderstood.
The RFM95s VCC is factory-wired to a regulator on the moteino. It is an out of the box MCU+Radio-Unit.
See this link for clarification:
Moteino with RFM95

Sorry for the confusion.

EDIT: I just tried changing my normal 433MHz Gateway with Arduino Nano + RFM69HCW on the RPi for a Moteino-integrated-RFM69HCW one.
I have the same problem with that as with the LoRa Moteino GW... It works fine with the PC and even gets readings far away, I normally do not get.
Hooking it up to the RPi with FHEM it stops working...
I can't really explain that?

EDIT 2: I checked the debug of the sensor-sided unit. It says st=OK...
So I guess I'll have to check my hardware (FTDI etc.)

@gohan
I am powering the sensor-sided Moteino with 3AA batteries.

When I unplug the 433MHz-Gateway from the RPi I at least get an autocreate and exactly one temperature reading.
Then it is dead again

Hi,
I don't know whether this helps, but I am also experiencing some trouble testing an RFM95 module.
I am using the Moteino with FTDI adapter.
I found that the connection is really instable (I should use some capacitors for a more stable connection I guess, even though there's no problem with the RFM69 433mHz version).
My configuration is the default one. Don't know if I even have to define it that way, just did it because I had to with the last ones:

#define MY_DEBUG                                  // used by MySensor (Print debug messages via serial)
#define MY_RADIO_RFM95                            // Select Radio-Module RFM95
#define MY_RFM95_FREQUENCY 868            // Define our Frequency of 868 MHz
#define MY_RFM95_MODEM_CONFIGRUATION RFM95_BW125CR45SF128 //Default for medium Range and medium speed: RFM95_BW125CR45SF128 ; For long range and slow speed: RFM95_BW125CR48SF4096
#define MY_RFM95_NETWORKID 100                  // leave out for gateway selection
#define   MY_RFM95_IRQ_PIN   DEFAULT_RFM95_IRQ_PIN
#define MY_RFM95_IRQ_NUM   DEFAULT_RFM95_IRQ_NUM
#define MY_RFM95_CS_PIN   DEFAULT_RFM95_CS_PIN
#define MY_NODE_ID 224                            // Node ID
#define MY_BAUD_RATE 38400

Also I am trying to use it with an RPi and FHEM. But this didn't work so far.
But I do get it to work over the PC-USB using the Arduino Serial-Monitor... Strange.

Hi, I am also trying to get them to work and stumbled upon this. I will try that and let you know if it works.

@webzter30 I guess he connected it to RST on the Adafruit-board. He mentioned that before. And the breakout does work with 3-5V, so it should work with almost anything. But Adafruit stated that you should use the same power on VIN as on the logic circuits. So for a Nano that would be 5V

EDIT: Works for me! Thanks.

Hey guys aside from these power-consumption issues, I am now running the Feather as gateway and node.
And I get a strange problem.
The gateway is attached to a raspberry pi via usb (by-id), which runs fhem. And everything works great for about an hour to 1 1/2. Then somehow the gateway stops receiving/communicating. I already tried an active USB-Hub incase the power consumption was too high for too long. But that didn't help. I have to reset the gateway and node to make it work again.
Did anybody else ever experience similar behaviour?

@NeverDie
Yes it was essentially the same sketch. I guess the 3.3 V regulator is consuming some power as well?
I would love to see it consuming even less power. But as long as it holds for about 3 months on 4500 mAh it is kind of OK for my purposes.
It would be great if you could measure it with your gear and maybe you have an idea how to get it even lower, since I also have to work on some peripheral stuff first. I am looking forward to hear from your tests.

@scalz
To be honest I am a little lost with all these abbreviations since I just started on working with MCUs, but I guess it is to make a point of "features need power"? But I will use these as hints as where to look for more saving potential.