@Yveaux Yes, it works now.

@Yveaux Thanks for that - I checked my cabling again and discovered a "hairline connection" between D3 and DTR. It is working better now.

I have a weird problem with a sensebender micro.
Loaded the standard sensebender sketch and all works fine.
Then I added a switch between 3.3V and D3 and initialized this with:
setup()
...
pinMode(MOTION_PIN, INPUT);
digitalWrite(MOTION_PIN, HIGH);
...

Now comes the weird part:
Whenever I press the D3 button, the sketch restarts. No matter if I sleep with interrupt or without etc.
If the serial console is NOT attached, it looks like the sketch continue to run.

I would assume some power issue, but for this test the board is powered over the USB-serial converter with 3.3V and everything else is working with or without opening the serial monitor in the Arduino Application.

Any idea what I am doing wrong?

According to this thread (https://forum.mysensors.org/topic/1573/my-generic-room-senser-sensebender-with-motion-and-light) I have tried to put a 25k resistor between D3 and ground, but without difference.

@Anticimex Thanks for your help!

@Anticimex I have checked out the signing branch and recompiled:

root@automation:/usr/local/src/MySensors# ./bin/mysgw -d
mysgw: Starting gateway...
mysgw: Protocol version - 2.2.0-beta
mysgw: MCO:BGN:INIT GW,CP=RNNG-SQ-,VER=2.2.0-beta
mysgw: SGN:PER:OK
mysgw: SGN:INI:BND OK
mysgw: TSF:LRT:OK
mysgw: TSM:INIT
mysgw: TSF:WUR:MS=0
mysgw: TSM:INIT:TSP OK
mysgw: TSM:INIT:GW MODE
mysgw: TSM:READY:ID=0,PAR=0,DIS=0
mysgw: MCO:REG:NOT NEEDED
mysgw: Listening for connections on 0.0.0.0:5003
mysgw: MCO:BGN:STP
mysgw: MCO:BGN:INIT OK,TSP=1
mysgw: New connection from 127.0.0.1
mysgw: Client 0 connected
mysgw: Client 0 disconnected
mysgw: Ethernet client disconnected.
mysgw: New connection from 127.0.0.1
mysgw: Client 0 connected
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 255;255;3;0;20;
mysgw: SGN:SKP:MSG CMD=3,TYPE=20
mysgw: TSF:MSG:SEND,0-0-255-255,s=255,c=3,t=20,pt=0,l=0,sg=0,ft=0,st=OK:
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;
mysgw: TSF:MSG:READ,101-101-255,s=255,c=3,t=7,pt=0,l=0,sg=0:
mysgw: TSF:MSG:BC
mysgw: TSF:MSG:FPAR REQ,ID=101
mysgw: TSF:PNG:SEND,TO=0
mysgw: TSF:CKU:OK
mysgw: TSF:MSG:GWL OK
mysgw: SGN:SKP:MSG CMD=3,TYPE=8
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=8,pt=1,l=1,sg=0,ft=0,st=OK:0
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=24,pt=1,l=1,sg=0:1
mysgw: SGN:SKP:MSG CMD=3,TYPE=24
mysgw: TSF:MSG:PINGED,ID=101,HP=1
mysgw: SGN:SKP:MSG CMD=3,TYPE=25
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=25,pt=1,l=1,sg=0,ft=0,st=OK:1
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=15,pt=6,l=2,sg=0:0101
mysgw: SGN:SKP:MSG CMD=3,TYPE=15
mysgw: SGN:PRE:SGN REQ,FROM=101
mysgw: SGN:PRE:SGN REQ,TO=101
mysgw: SGN:PRE:WHI NREQ,TO=101
mysgw: SGN:SKP:MSG CMD=3,TYPE=15
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=15,pt=6,l=2,sg=0,ft=0,st=OK:0101
mysgw: SGN:PRE:XMT,TO=101
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=16,pt=0,l=0,sg=0:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=17,pt=6,l=25,sg=0,ft=0,st=OK:<NONCE>
mysgw: SGN:NCE:XMT,TO=0
mysgw: Client 0: 0;255;3;0;2;
mysgw: TSF:MSG:READ,101-101-0,s=255,c=0,t=17,pt=0,l=5,sg=1:2.1.1
mysgw: SGN:BND:NONCE=BE1E788A73D8B77B73E8222D5A3631E99FC1157CC969C6A324AAAAAAAAAAAAAA
mysgw: SGN:BND:HMAC=A50A32E714615D7559D01B4A71B86D59160FAD437C1A0A57C1D6A51BC4410E66
mysgw: SGN:VER:OK
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=16,pt=0,l=0,sg=1:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=17,pt=6,l=25,sg=1,ft=0,st=OK:<NONCE>
mysgw: SGN:NCE:XMT,TO=0
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=6,pt=1,l=1,sg=1:0
mysgw: SGN:BND:NONCE=83B9D811BA4341EEDD7D28B1D0ED0841305E58110879203AE2AAAAAAAAAAAAAA
mysgw: SGN:BND:HMAC=D48A08AA586888933B2EA56857AE12BB353875C726FC8923CFDBE38C888F5EBB
mysgw: SGN:VER:OK
mysgw: Client 0: 101;255;3;0;6;M
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=16,pt=0,l=0,sg=0,ft=0,st=OK:
mysgw: SGN:SGN:NCE REQ,TO=101
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=17,pt=6,l=25,sg=0:<NONCE>
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: SGN:NCE:FROM=101
mysgw: SGN:BND:NONCE=41DDA29AC9224192AD697FA3D433003E60DC319EA8A6014B60AAAAAAAAAAAAAA
mysgw: SGN:BND:HMAC=86EAC3CDC63F39CF0F333082CF68A66555468D14BBD4AC3E546F8EE773C580C6
mysgw: SGN:SGN:SGN
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=6,pt=0,l=1,sg=1,ft=0,st=OK:M
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=16,pt=0,l=0,sg=1:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=17,pt=6,l=25,sg=1,ft=0,st=OK:<NONCE>
mysgw: SGN:NCE:XMT,TO=0
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=11,pt=0,l=14,sg=1:Nano Motion FW
mysgw: SGN:BND:NONCE=D3676555B4228F26DC34A6B43947B41439156EA5112DC17370AAAAAAAAAAAAAA
mysgw: SGN:BND:HMAC=EBF256F5C55B9FE8FB5FE9A7FBB22C569D782DB73998661FD66D639049D1E624
mysgw: SGN:VER:OK
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=16,pt=0,l=0,sg=1:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=17,pt=6,l=25,sg=1,ft=0,st=OK:<NONCE>
mysgw: SGN:NCE:XMT,TO=0
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=12,pt=0,l=3,sg=1:1.1
mysgw: SGN:BND:NONCE=08F1450783D33257E28EC8B01E0ECE93A41D2826F3972F99EBAAAAAAAAAAAAAA
mysgw: SGN:BND:HMAC=33B02115FA75F8E708B50E825853E80D3A70D5F804FB7E27242B357CF043F8D1
mysgw: SGN:VER:OK
mysgw: TSF:MSG:READ,101-101-0,s=1,c=3,t=16,pt=0,l=0,sg=1:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=17,pt=6,l=25,sg=1,ft=0,st=OK:<NONCE>
mysgw: SGN:NCE:XMT,TO=0
mysgw: TSF:MSG:READ,101-101-0,s=1,c=0,t=6,pt=0,l=0,sg=1:
mysgw: SGN:BND:NONCE=BAD7253134C6C7F0C0B79FFBF41914B2E0AB59DFDAB7874678AAAAAAAAAAAAAA
mysgw: SGN:BND:HMAC=5BF1F9D417EB97A3C5E7880F18A839EAA464D21FE6A2F7B2D32A3C3431A7A00B
mysgw: SGN:VER:OK
mysgw: TSF:MSG:READ,101-101-0,s=2,c=3,t=16,pt=0,l=0,sg=1:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=17,pt=6,l=25,sg=1,ft=0,st=OK:<NONCE>
mysgw: SGN:NCE:XMT,TO=0
mysgw: TSF:MSG:READ,101-101-0,s=2,c=0,t=7,pt=0,l=0,sg=1:
mysgw: SGN:BND:NONCE=70410E6BD4E2E3298F348801747889920E2F5779BC0474A7D2AAAAAAAAAAAAAA
mysgw: SGN:BND:HMAC=8632A9E570D1EEEBF766CC7E25C82CD06EB58F21FC0ED3CECF8FCD8B84473379
mysgw: SGN:VER:OK
mysgw: TSF:MSG:READ,101-101-0,s=4,c=3,t=16,pt=0,l=0,sg=1:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=17,pt=6,l=25,sg=1,ft=0,st=OK:<NONCE>
mysgw: SGN:NCE:XMT,TO=0
mysgw: TSF:MSG:READ,101-101-0,s=4,c=0,t=1,pt=0,l=0,sg=1:
mysgw: SGN:BND:NONCE=54C9C968967021485E45AA2047EA666C63062BFCFFDBC19423AAAAAAAAAAAAAA
mysgw: SGN:BND:HMAC=1397236B072105342EA4CBBBD555B356C2022B8EB64ABBFA637781F6720483A1
mysgw: SGN:VER:OK
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=26,pt=1,l=1,sg=1:2
mysgw: SGN:SKP:MSG CMD=3,TYPE=26
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=16,pt=0,l=0,sg=1,ft=0,st=OK:
mysgw: SGN:SGN:NCE REQ,TO=101
mysgw: TSF:MSG:READ,101-101-0,s=255,c=3,t=17,pt=6,l=25,sg=1:<NONCE>
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: SGN:NCE:FROM=101
mysgw: SGN:BND:NONCE=D1294AF646074EC7CCD7CD6B02BC4619EF79B0A915648A6A07AAAAAAAAAAAAAA
mysgw: SGN:BND:HMAC=127FCE6A3EF3FB0906A20BF3128A318801C5167F215ABAF4EEC0A595AFD373FB
mysgw: SGN:SGN:SGN
mysgw: TSF:MSG:SEND,0-0-101-101,s=255,c=3,t=27,pt=1,l=1,sg=1,ft=0,st=OK:1
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;

@Anticimex

mysgw: Starting gateway...
mysgw: Protocol version - 2.2.0-beta
mysgw: MCO:BGN:INIT GW,CP=RNNG-SQ-,VER=2.2.0-beta
mysgw: SGN:PER:OK
mysgw: SGN:PER:OK
mysgw: TSF:LRT:OK
mysgw: TSM:INIT
mysgw: TSF:WUR:MS=0
mysgw: TSM:INIT:TSP OK
mysgw: TSM:INIT:GW MODE
mysgw: TSM:READY:ID=0,PAR=0,DIS=0
mysgw: MCO:REG:NOT NEEDED
mysgw: Listening for connections on 0.0.0.0:5003
mysgw: MCO:BGN:STP
mysgw: MCO:BGN:INIT OK,TSP=1
mysgw: New connection from 127.0.0.1
mysgw: Client 0 connected
mysgw: Client 0: 255;255;3;0;20;
mysgw: SGN:SKP:MSG CMD=3,TYPE=20
mysgw: TSF:MSG:SEND,0-0-255-255,s=255,c=3,t=20,pt=0,l=0,sg=0,ft=0,st=OK:
mysgw: Client 0: 0;255;3;0;2;
mysgw: TSF:MSG:READ,198-198-0,s=255,c=3,t=21,pt=1,l=1,sg=0:0
mysgw: SGN:SKP:MSG CMD=3,TYPE=21
mysgw: Client 0: 0;255;3;0;2;
mysgw: Client 0: 0;255;3;0;2;
mysgw: TSF:MSG:READ,100-100-255,s=255,c=3,t=7,pt=0,l=0,sg=0:
mysgw: TSF:MSG:BC
mysgw: TSF:MSG:FPAR REQ,ID=100
mysgw: TSF:PNG:SEND,TO=0
mysgw: TSF:CKU:OK
mysgw: TSF:MSG:GWL OK
mysgw: SGN:SKP:MSG CMD=3,TYPE=8
mysgw: TSF:MSG:SEND,0-0-100-100,s=255,c=3,t=8,pt=1,l=1,sg=0,ft=0,st=OK:0
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=24,pt=1,l=1,sg=0:1
mysgw: SGN:SKP:MSG CMD=3,TYPE=24
mysgw: TSF:MSG:PINGED,ID=100,HP=1
mysgw: SGN:SKP:MSG CMD=3,TYPE=25
mysgw: TSF:MSG:SEND,0-0-100-100,s=255,c=3,t=25,pt=1,l=1,sg=0,ft=0,st=OK:1
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=15,pt=6,l=2,sg=0:0101
mysgw: SGN:SKP:MSG CMD=3,TYPE=15
mysgw: SGN:PRE:SGN REQ,FROM=100
mysgw: !SGN:PRE:WHI NREQ,FROM=100 REJ
mysgw: SGN:PRE:SGN REQ,TO=100
mysgw: SGN:PRE:WHI NREQ,TO=100
mysgw: SGN:SKP:MSG CMD=3,TYPE=15
mysgw: TSF:MSG:SEND,0-0-100-100,s=255,c=3,t=15,pt=6,l=2,sg=0,ft=0,st=OK:0101
mysgw: SGN:PRE:XMT,TO=100
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=16,pt=0,l=0,sg=0:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: !SGN:NCE:GEN
mysgw: Client 0: 0;255;3;0;2;

PS:
I am on Skype with the same Nick if you want more synchronous communication.

@Anticimex I did:
git clone https://github.com/mysensors/MySensors.git --branch development
cd MySensors
git pull https://github.com/fallberg/MySensors.git signing

Then compile with:
./configure --my-gateway=ethernet
--my-transport=nrf24
--my-rf24-ce-pin=22
--my-rf24-cs-pin=24
--my-rf24-irq-pin=15
--my-rf24-pa-level=RF24_PA_LOW
--my-leds-err-pin=12
--my-leds-rx-pin=16
--my-leds-tx-pin=18
--my-rf24-channel=76
--my-debug=enable
--my-signing=software
--my-signing-request-signatures
--my-signing-request-gw-signatures-from-all
--my-signing-debug

Result with one node restarting while others are already running:

mysgw: TSF:MSG:READ,100-100-255,s=255,c=3,t=7,pt=0,l=0,sg=0:
mysgw: TSF:MSG:BC
mysgw: TSF:MSG:FPAR REQ,ID=100
mysgw: TSF:PNG:SEND,TO=0
mysgw: TSF:CKU:OK
mysgw: TSF:MSG:GWL OK
mysgw: SGN:SKP:MSG CMD=3,TYPE=8
mysgw: TSF:MSG:SEND,0-0-100-100,s=255,c=3,t=8,pt=1,l=1,sg=1,ft=0,st=OK:0
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=24,pt=1,l=1,sg=0:1
mysgw: SGN:SKP:MSG CMD=3,TYPE=24
mysgw: TSF:MSG:PINGED,ID=100,HP=1
mysgw: SGN:SKP:MSG CMD=3,TYPE=25
mysgw: TSF:MSG:SEND,0-0-100-100,s=255,c=3,t=25,pt=1,l=1,sg=1,ft=0,st=OK:1
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=15,pt=6,l=2,sg=0:0101
mysgw: SGN:SKP:MSG CMD=3,TYPE=15
mysgw: SGN:PRE:SGN REQ,FROM=100
mysgw: !SGN:PRE:WHI NREQ,FROM=100 REJ
mysgw: SGN:PRE:SGN REQ,TO=100
mysgw: SGN:PRE:WHI NREQ,TO=100
mysgw: SGN:SKP:MSG CMD=3,TYPE=15
mysgw: TSF:MSG:SEND,0-0-100-100,s=255,c=3,t=15,pt=6,l=2,sg=0,ft=0,st=OK:0101
mysgw: SGN:PRE:XMT,TO=100
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=16,pt=0,l=0,sg=0:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: !SGN:NCE:GEN
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=16,pt=0,l=0,sg=0:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: !SGN:NCE:GEN
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=16,pt=0,l=0,sg=0:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: !SGN:NCE:GEN
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=16,pt=0,l=0,sg=0:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: !SGN:NCE:GEN
mysgw: TSF:MSG:READ,100-100-0,s=1,c=3,t=16,pt=0,l=0,sg=0:
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: !SGN:NCE:GEN
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=26,pt=1,l=1,sg=0:2
mysgw: SGN:SKP:MSG CMD=3,TYPE=26
mysgw: SGN:SKP:MSG CMD=3,TYPE=16
mysgw: TSF:MSG:SEND,0-0-100-100,s=255,c=3,t=16,pt=0,l=0,sg=1,ft=0,st=OK:
mysgw: SGN:SGN:NCE REQ,TO=100
mysgw: TSF:MSG:READ,100-100-0,s=255,c=3,t=17,pt=6,l=25,sg=1:<NONCE>
mysgw: SGN:SKP:MSG CMD=3,TYPE=17
mysgw: SGN:NCE:FROM=100
mysgw: SGN:BND:NONCE=4BD28D2B47813291B354D4A856B07E7A6B496CF86FA2FF969D7C2D115FAC09DF
mysgw: SGN:BND:HMAC=07FF305FFEB4D1489C3C9BA63A281890DDD850573B406FB691C09C23DC12DD00
mysgw: SGN:BND:SIG WHI,ID=0
mysgw: SGN:BND:SIG WHI,SERIAL=000000000000000000
mysgw: SGN:SGN:SGN
mysgw: TSF:MSG:SEND,0-0-100-100,s=255,c=3,t=27,pt=1,l=1,sg=1,ft=0,st=OK:1

Looks OK for me, right?

@Anticimex Sure, can do.
Would you refresh my memory - how can I check out the tree with that pullrequest?

@Anticimex Well, I have read all troubleshooting material many times and agree that mostly it is HW. This time however it was stupidity on my side!
I mixed up signing with encryption on the Pi compile time flags.
To summarize:
On 2.1.1, the architecture needs to be set and signing works (have not tested encryption yet).
On dev, architecture needs to be left alone (not set) and checksum calculation needs to be commented out (line 127 of MySigningAtsha204Soft.cpp).

@Anticimex Have tried to comment out line 127, but as you said no joy. I know that the radio I am using is not the best but I am still not sure if the HW is the culprit here.

I have put that RF24 module onto a Nano with itead RF Shield and loaded a 2.1.1 Gateway Sketch including signing - that works against the same node I am testing the Pi.
I am using the interrupt variant of the Pi cabling - could that be the problem?