Code Snippets

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Sending messages with netcat

The Linux command netcat makes it very easy to send messages from a Raspberry Pi to a Bticino Gateway. The syntax is:

pi@raspberry ~ $ echo "<message>" | netcat <gateway-IP> <gateway-port>

For example: turn off light 94 (9.4) on interface 5:

pi@raspberry ~ $ echo "*1*0*94#4#05##" | netcat 192.168.1.55 20000

A Python Monitor Session with Bticino Gateway

To understand the OWN messages better, you should start a monitor session and watch the OWN messages flying in from your home automation system. Analyzing these messages gives you an idea how it works. Below is a simple monitor script in Python.

For Raspberry Pi

Start editor an editor (in our example nano) and create monitor.py

nano monitor.py

Copy and paste the script below into that file and save it. After you saved the file, you have to make the file executable:

chmod 755 monitor.py

Now start the monitor and watch the messages fly by. Exit with CTRL-C.

./monitor.py

For Windows

Download and install Python for Windows and create the file monitor.py and edit with an text editor. Copy and paste the source code below in that file and save it. Then just double click monitor.py.

The Python Script monitor.py

Copy the content of this script to monitor.py

#!/usr/bin/python
# -*- coding: utf-8 -*-
import socket
 
gateway_host = "192.168.60.201"     # set here the IP of your gateway
gateway_port = 20000                # set here the port of your gateway
 
gateway_addr_port = gateway_host, gateway_port
 
def monitor():
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    try:
        sock.connect(gateway_addr_port)
        data = sock.recv(1024)
        if data != "*#*1##":        # expect ACK from gateway
            raise Exception("Did not receive expected ACK, but: "+data)
        sock.send("*99*1##")        # Switch session to MONITOR mode
        data = ""
        while 1:
            next = sock.recv(1024)  # now read data from MyHome BUS
            if next == "":
                break               # EOF
            data = data + next
            eom = data.find("##")
            if eom < 0:
                continue;           # Not a complete message, need more
            if data[0] != "*":
                raise Exception("Message does not start with '*': "+data)
            msg = data[0:eom+2]     # message is from position 0 until end of ##
            data = data[eom+2:]     # next message starts after ##
            print msg
    finally:
        sock.close()
 
monitor()                           # start the monitor