@ikkeT you can build the Raspberry Pi mysGateway as either Serial, Ethernet or MQTT by using appropriate commandline parameters with the configure script. Just do ./configure --help and you'll get a list of all the options available. Once you've chosen your options and run configure then you 'make'. An example of a set of options that will generate an MQTT Gateway is:
./configure --my-debug=enable --my-gateway=mqtt --my-rf24-channel=100 --my-rf24-pa-level=RF24_PA_LOW --my-controller-ip-address=127,0,0,1 --my-port=1883
--my-mqtt-client-id=MyGW2 --my-mqtt-publish-topic-prefix="MyGW2out" --my-mqtt-subscribe-topic-prefix="MyGW2in"

In this case my MQTT Broker is Mosquitto and is on the same Raspberry Pi hence the use of 127,0,0,1 for the specified --my-controller-ip-address. Change that as appropriate to your intended setup.

Hope that helps.

@marceloaqno I second @frencho's comment, excellent job on getting mainline support for the Raspberry Pi into the MySensors codebase. Thank you for your efforts.

@ikkeT you can build the Raspberry Pi mysGateway as either Serial, Ethernet or MQTT by using appropriate commandline parameters with the configure script. Just do ./configure --help and you'll get a list of all the options available. Once you've chosen your options and run configure then you 'make'. An example of a set of options that will generate an MQTT Gateway is:
./configure --my-debug=enable --my-gateway=mqtt --my-rf24-channel=100 --my-rf24-pa-level=RF24_PA_LOW --my-controller-ip-address=127,0,0,1 --my-port=1883
--my-mqtt-client-id=MyGW2 --my-mqtt-publish-topic-prefix="MyGW2out" --my-mqtt-subscribe-topic-prefix="MyGW2in"

In this case my MQTT Broker is Mosquitto and is on the same Raspberry Pi hence the use of 127,0,0,1 for the specified --my-controller-ip-address. Change that as appropriate to your intended setup.

Hope that helps.

@marceloaqno The mechanism for assigning the pty serial port the specified group ownership doesn't appear to be working. The pty port is always created with root:root ownership. Can you (or anyone else) confirm whether this is working for you? I'm on a Raspberry Pi 2 running Raspian Jessie. Thanks.

@marceloaqno I've got the MysGateway configured and built to be an MQTT Gateway. I have a node (MySensors v2.01) sending temperature, humidity and voltage data to the Gateway. Looking at the stdout on the Raspberry Pi I can see that the information is being correctly received but there seems to be a problem with the published messages. I'm getting "send: Broken pipe" messages. I've copied and pasted some of the MysGateway stdout terminal output below. Do you have any insights on what might be going wrong?

Thanks very much

Sending message on topic: MyGW2out/0/255/0/0/18
TSF:MSG:READ,20-20-255,s=255,c=3,t=7,pt=0,l=0,sg=0:
TSF:MSG:BC
TSF:MSG:FPAR REQ,ID=20
TSF:CHKUPL:OK
TSF:MSG:GWL OK
TSF:MSG:SEND,0-0-20-20,s=255,c=3,t=8,pt=1,l=1,sg=0,ft=0,st=OK:0
TSF:MSG:READ,20-20-0,s=255,c=3,t=24,pt=1,l=1,sg=0:1
TSF:MSG:PINGED,ID=20,HP=1
TSF:MSG:SEND,0-0-20-20,s=255,c=3,t=25,pt=1,l=1,sg=0,ft=0,st=OK:1
TSF:MSG:READ,20-20-0,s=255,c=3,t=12,pt=0,l=3,sg=0:0.5
Sending message on topic: MyGW2out/20/255/3/0/12
send: Broken pipe
Attempting MQTT connection...
MQTT connected
Sending message on topic: MyGW2out/0/255/0/0/18
TSF:MSG:READ,20-20-0,s=2,c=0,t=23,pt=0,l=0,sg=0:
Sending message on topic: MyGW2out/20/2/0/0/23
TSF:MSG:READ,20-20-0,s=255,c=3,t=26,pt=1,l=1,sg=0:2
TSF:MSG:SEND,0-0-20-20,s=255,c=3,t=27,pt=1,l=1,sg=0,ft=0,st=OK:1
TSF:MSG:READ,20-20-0,s=1,c=1,t=0,pt=7,l=5,sg=0:19.9
Sending message on topic: MyGW2out/20/1/1/0/0
send: Broken pipe
Attempting MQTT connection...
MQTT connected
Sending message on topic: MyGW2out/0/255/0/0/18
TSF:MSG:READ,20-20-0,s=2,c=1,t=38,pt=7,l=5,sg=0:3319.0
Sending message on topic: MyGW2out/20/2/1/0/38
send: Broken pipe
Attempting MQTT connection...
MQTT connected
Sending message on topic: MyGW2out/0/255/0/0/18
TSF:MSG:READ,20-20-0,s=0,c=1,t=1,pt=7,l=5,sg=0:58.6
Sending message on topic: MyGW2out/20/0/1/0/1
send: Broken pipe
Attempting MQTT connection...
MQTT connected
Sending message on topic: MyGW2out/0/255/0/0/18

Yes indeed there is, check out the great work by marceloaqno, https://github.com/marceloaqno/MySensors.git
He says that this fork is destined to become part of the MySensors codebase soon.

@ExParrot_NZ

You don't mention whether you're using the MySensors library on your Arduino, however my assumption is that you are. Have you checked the obvious, that the Raspberry Pi (being used to transmit) has configured the nRF24 data rate to be the same as your Arduino's nRF24 is expecting? I note that you're using the highest data rate setting of 2Mbps on the RPi transmit side of things. By default the MySensors library on the Arduino side will configure the nRF24 for 250Kbps, unless you have remembered to over ride that.

Just a thought!

@Bens, You should find that once you run a script, or controller of some kind that connects to the virtual serial port that PiGatewaySerial provides, CPU usage (as reported in top) will drop way down. What you're seeing, in my experience, isn't an actual problem, just an apparent one!

Cheers
Richard

@GuyP Do you have a favourite seller for those mega328 DIP parts? Mostly when I've looked on eBay the clone Arduino Mini's come in cheaper than a DIP package mega328 IC. I also would prefer to use a design that utilises the mega328 DIP directly rather than an Arduino Mini if I could. Cost per node is very important to me to enable affordable expansion of my network. Thanks.

@tbowmo, ah, sorry misunderstanding then. I thought it was the atsha204 that was contributing 30% of the cost, but I guess it's the Si7021, which is rather useful to have!

I'll add my voice to the requests for a 'lite' version of the Sensebender Micro board. My ideal would be to provide an option without the A20 secure signing IC placed, but leaving the Si7021 in.

Cheers
Richard