HINT
For developing remote on the raspberry pi with vscode in your local machine with root permissions:

1. install vscode extension ssh-remote
2. on the remote machine (raspberry) add this at the end of /etc/ssh/sshd_conf:

# Allow root login only for localhost
Match Address 127.0.0.1
        PermitRootLogin yes

3. Type this in the raspi terminal sudo systemctl restart sshd.service
4. Go to the ssh-remote extension tab in the vscode of your local machine and start a connection to the remote raspberry pi
5. Go to the extensions tab in vscode. Now you can install your local vscode extensions in your remote machine

FUNCTIONALITY DESCRIPTION

The core of the KNX URL Gateway consists of a server that handle URL´s in this form:
http://ipaddressofthegateway:1234/knx/group/address-value

Valid values are an for switch on, aus for switch off, plus for dimm up and minus for dimm down.

If there is an incoming request in this form, the server:

• looks if the KNX groupaddress is in the stored .csv file (this file contains all information about all groupaddresses of the KNX installation and can be exported from the KNX programming tool ETS)

• looks in the .csv file for the datapointtype (for instance only boolean/DPT1 and relative dimming/DPT3) and calls the proper method for building the KNX dataframe (Telegram) with the specified value in the URL, if the groupaddress exists

• sends the built frame to the KNX bus

Here is a .csv file example.

CONFIGURING THE URL SERVER

The gateway folder must be saved in the device (prototype= raspberry pi) in the folder /usr/local/.

1. Add this in the /boot/config.txt of the raspberry pi:

   dtoverlay=pi3-miniuart-bt
   enable_uart=1
   force_turbo=1

2. Delete this in the file /boot/cmdline.txt: console=serial0,115200

3. Adjust the group of the device with:
   chgrp dialout /dev/ttyAMA0

4. Add the user in the group with:
   usermod -a -G dialout pi

5. Build and compile the sourcecode with cmake.

6. Create this cronjob:
   @reboot /usr/local/gateway/launcher.sh >/usr/local/gateway/cronlog 2>&1

7. Save the newest .csv file with your knx groupaddresses here:
   /usr/local/gateway, or use the GUI of this repo, after doing point 8.

8. Reboot the device

Reading KNX traffic:

• with the busmonitor script:
  see this repo (work in progress)
• with socat:
  sudo socat -x -u /dev/ttyAMA0,raw,echo=0,crnl PTY,link=/dev/ttyV1,raw,echo=1,crnl
• saving socat output to a file:
  sudo socat -x -u /dev/ttyAMA0,raw,echo=0,crnl PTY,link=/dev/ttyV1,raw,echo=1,crnl 2>&1 >/dev/null | tee knx_monitor.txt

Mantainer: Golpe Varela, Simón

2018 - current