Setup image and install tools for building your a KNX IP interface for ETS5 and 1-wire support.
Install Debian 10
Download and flash below image to a 2GB micro-SD card.
https://rcn-ee.net/rootfs/2020-04-09/flasher/bone-eMMC-flasher-debian-10.3-console-armhf-2020-04-09-2gb.img.xz
Now that you have the latest image of Angstrom loaded onto your micro-SD card slot, you'll need to flash it onto the on-board flash memory of the BeagleBone Black.
To start, make sure the BeagleBone Black is powered down, and unplugged from the power source.
Now, insert the micro-SD card into the slot on the back of the BeagleBone Black. It should snap into place.
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Hold the "User Boot" button down, and then plug in the power (USB or 5V adapter). Keep holding down the button until you see the bank of 4 LED's light up for a few seconds. You can now release the button.
It will take anywhere from 30-45 minutes to flash the image onto the on-board chip. Once it's done, the bank of 4 LED's to the right of the Ethernet will all turn off. You can then power down your BeagleBone Black. Remove card and place Cape back, power on.
Setup image
# Look for bbgw's IP address in DHCP and login using SSH
ssh 192.168.178.122
Pre-authentication banner message from server:
| Debian GNU/Linux 10
|
| rcn-ee.net Debian Console Image 2020-04-09
|
| Support: http://elinux.org/BeagleBoardDebian
|
| default username:password is [debian:temppwd]
|
End of banner message from server
# Set password for root user
$ sudo passwd root
$ sudo useradd -m -s /bin/bash -c "Full Name" -U user
$ sudo passwd user
$ sudo usermod -aG sudo,dialout user
# Logout/in
$ sudo userdel --remove debian
# Remove banners
$ sudo rm /etc/issue*
cat <<EOF >update.sh
#!/bin/bash
sudo apt-get update
sudo apt-get upgrade
sudo apt-get autoclean
sudo apt-get clean
sudo apt-get autoremove
> ~/.bash_history
history -c
dpkg -l | awk '/^rc/ {print $2}' | xargs sudo dpkg --purge
EOF
$ chmod +x install.sh
$ ./update/sh
$ sudo dpkg-reconfigure tzdata
$ sudo reboot
Install and configure the 1-wire daemon
$ sudo apt-get install owserver owhttpd owfs
$ sudo vi /etc/owfs.conf
# Create 1wire mountpoint
$ sudo mkdir /mnt/1wire
# Replace line with „FAKE“ with" these:
server: i2c = dev/i2c-2:0
server: i2c = dev/i2c-3:0
server: i2c = dev/i2c-4:0
server: i2c = dev/i2c-5:0
# Edit settings for owfs
mountpoint = /mnt/1wire
allow_other
$ sudo service owserver start
$ sudo service owhttpd start
# Browse to http://[IP]:2121 click „bus.0“ you should see the onboard Temperature sensor „28.xxxxxxx“
$ cat /mnt/1wire/28.FFAB96641401/temperature
28.1875
Install and configure the knxd daemon.
$ sudo apt-get install knxd knxd-tools
# Set static IP address and defince multicast routes
$ sudo vi /etc/network/interfaces
iface eth0 inet static
address 192.168.2.30
netmask 255.255.255.0
gateway 192.168.2.254
post-up route add -net 224.0.23.12 netmask 255.255.255.255 eth0
pre-down route del -net 224.0.23.12 netmask 255.255.255.255 eth0
$ cat /etc/resolv.conf
nameserver 192.168.2.254
nameserver 8.8.8.8
$ sudo apt purge connman
$ sudo reboot
# Testing params
$ sudo service knxd stop
$ knxd --eibaddr=1.1.200 --client-addrs=1.1.201:8 -D -T -R -S -i --listen-local=/tmp/knx -t 1023 -b tpuart:/dev/ttyO2
# You can create the content of the ini file by running the following command.
$ /usr/lib/knxd_args --eibaddr=1.1.200 --client-addrs=1.1.201:8 -D -T -R -S --listen-local=/tmp/knx -t 1023 -b tpuart:/dev/ttyO2
[A.unix]
path = /tmp/knx
server = knxd_unix
systemd-ignore = false
[B.tpuart]
debug = debug-B.tpuart
device = /dev/ttyO2
driver = tpuart
[debug-B.tpuart]
trace-mask = 0x3ff
[debug-main]
trace-mask = 0x3ff
[debug-server]
name = mcast:knxd
[main]
addr = 1.1.200
client-addrs = 1.1.201:8
connections = server,A.unix,B.tpuart
debug = debug-main
systemd = systemd
[server]
debug = debug-server
discover = true
router = router
server = ets_router
tunnel = tunnel
Give permission to knxd
$ sudo usermod -a -G tty knxd
$ sudo usermod -a -G dialout knxd
$ sudo vi /etc/knxd.ini
[A.unix]
path = /tmp/knx
server = knxd_unix
systemd-ignore = false
[B.tpuart]
debug = debug-B.tpuart
device = /dev/ttyO2
driver = tpuart
[debug-B.tpuart]
trace-mask = 0x3ff
[debug-server]
name = mcast:knxd
[main]
addr = 1.1.200
client-addrs = 1.1.201:8
connections = server,A.unix,B.tpuart
systemd = systemd
[server]
debug = debug-server
discover = true
router = router
server = ets_router
tunnel = tunnel
$ sudo vi /etc/knxd.conf
# configuration for knxd.service
#KNXD_OPTS="-e 0.0.1 -E 0.0.2:8 -u /tmp/eib -b ip:"
# configuration for knxd.service using new configuration format in /etc/knxd.ini
# use only this line if you used knxd_args to convert your old startup options
KNXD_OPTS=/etc/knxd.ini
$ sudo service knxd restart
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Publish 1-Wire temperature sensor values on bus
NOTE: you need to find your sensor ID and adjust script below (behind "/mnt/1wire/"
$ vi knxtemp.sh
#!/usr/bin/env python3
# knxtemp.py. This script sends the measured temperature as DPT9 to the KNX bus
import os
import struct
file=open('/mnt/1wire/28.FFAB96641401/temperature','r')
tmp = '{:.2f}'.format(float(file.read()))
def to_knx(value):
def calc_exponent(float_value, sign):
"""Return float exponent."""
exponent = 0
significand = abs(int(float_value * 100))
while significand < -2048 or significand > 2048:
exponent += 1
significand >>= 1
if sign:
significand ^= 0x7FF
significand += 1
return exponent, significand
try:
knx_value = float(value)
sign = 1 if knx_value < 0 else 0
exponent, significand = calc_exponent(knx_value, sign)
return (sign << 7) | (exponent << 3) | (
significand >> 8
), significand & 0xFF
except ValueError:
print("Could not serialize %s", value)
byte_str = ""
for x in to_knx(tmp):
byte_str += hex(x)+ " "
file.close()
os.system('knxtool groupwrite ip:localhost 4/5/1 '+byte_str)
Configure crontab
# Run script every minute
$ crontab -e
# m h dom mon dow command
* * * * * /home/user/knxtemp.sh
Configure Home Assistant
knx:
...
sensor:
- name: Temperatuur BeagleBone
state_address: "4/5/1"
type: temperature
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