I used a mini pro whith FTDI :
It wasn't working the serial gateway don't send data.
I test with a nano and all is ok now ...
And on my relay sensor :
Terminal ready
req id
send: 255-255-0-0 s=255,c=3,t=3,pt=0,l=0,sg=0,st=ok:
read: 0-0-255 s=255,c=3,t=4,pt=0,l=1,sg=0:1
send: 1-1-0-0 s=255,c=0,t=18,pt=0,l=3,sg=0,st=ok:1.5
send: 1-1-0-0 s=255,c=3,t=6,pt=1,l=1,sg=0,st=ok:0
read: 0-0-1 s=255,c=3,t=6,pt=0,l=1,sg=0:M
id=1
send: 1-1-0-0 s=255,c=0,t=18,pt=0,l=3,sg=0,st=ok:1.5
send: 1-1-0-0 s=255,c=3,t=6,pt=1,l=1,sg=0,st=ok:0
read: 0-0-1 s=255,c=3,t=6,pt=0,l=1,sg=0:M
repeater started, id=1, parent=0, distance=1
send: 1-1-0-0 s=255,c=3,t=11,pt=0,l=5,sg=0,st=ok:Relay
send: 1-1-0-0 s=255,c=3,t=12,pt=0,l=3,sg=0,st=ok:1.0
send: 1-1-0-0 s=1,c=0,t=3,pt=0,l=0,sg=0,st=ok: