Creasol DomBus12 is a compact module, 40x30x11mm, with 9 configurable inputs/outputs.
It can be connected to the Domoticz controller by a RS485 serial bus (4 wires, 2 for 12/24V power supply, and 2 for data at 115200bps).

As other DomBus devices, DomBus12 is designed to consume low power, be reliable, fully configurable and easy to use. Each port is fully configurable, e.g. as analog or digital input, twinbutton (double button), counter, buzzer,  NTC 10k, ... 2 ports may be used as open-drain output, to activate 2 external relays or LEDs.

Features

• 4 configurable I/Os, each one can be set as analog/digital input, twinbutton input, counter, digital output (can be connected to external relay board within relay driver)
• 2 configurable I/Os, each one can be set as open-drain output (to be connected to external relay), blind output (to be connected to external relay), low power LED dimmer, analog/digital input: to set IO5 and/or IO6 as input the PCB jumper ROx must be opened (using a cutter) and RIx must be shorted (with a solder ball).
  
• 3 configurable I/Os, each one can be set as analog/digital inputs, counter, buzzer outputs, blind outputs (to be connected to external relay board), LED strip dimmer (to be connected to external mosfet)
• 7.5-35Vdc power supply (internally regulated by a switching mode power supply circuitry that minimize power consumption and dissipation)
• low power consumption: 0.7mA stand-by current at 12V (10mW)
• 115200 bps RS485 bus (max length: 1km)

Warnings

• Do not connect high voltage sources or loads to the DomBus12 wires: this device is designed to work with low voltage I/Os.
• Use a 4 wires shielded cable for the bus, using two lines to feed power supply (12 or 24Vdc) protected by a fuse.
• To reduce noise and reflections on the bus, enable the termination resistor (shorting Rbus PCB jumper) on the two furthest ends of the bus.

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DomBus12 Ports capabilities

Default address: 0xff12

(1): can be used as BLIND output, to open a blind/curtain, but only the previous port can be configured in Domoticz as OUT_BLIND because, when configured as OUT_BLIND, DomBus device automatically configure the next port to drive a relay in open direction.

Configuring IO5 and/or IO6 as input

IO5 and IO6 by default are configured as open-drain outputs: to configure those ports as input (to connect for example an external switch, a magnetic contact sensor or PIR, ...) a simple hardware modification have to be made, by opening the corresponding ROx pcb jumper (using a cutter to cut the small trace between the jumper pads) and shorting the corresponding RIx pcb jumper (using a solder iron with a small quantity of solder wire to make a short circuit).
For example, to set IO5 as input, open RO5 using a cutter, and make a short circuit on RI5 pads. Then, that port can be configured by software as digital or analog input by writing, in the Domoticz description, IN_DIGITAL or IN_ANALOG.

Using input ports to read external DC voltages

Voltages applied to a DomBus module input must be in the range 0-3.3Vdc, so an external resistive partition should be applied to measure higher voltage.
For example, to monitor a 12V voltage, a resistive partition with 100k and 22k can be used: in this case max applied voltage = 3.3 / 22k * (100k + 22k) = 18.3V and the A constant used in the domotic controller to get the real voltage is calculated as 18.3/65535=0.00027924
Please note that analog voltage can be applied only to module ports without the 10k pullup resistor: in DomBus12 IO7-IO9 can be used without any modification, IO1-IO4 can be used opening with a cutter the corresponding PCB jumper, and IO5-IO6 can be used configuring their jumpers in input mode (opening ROn and shorting RIn with the solder iron).
Take care to measure voltages only on devices that share the same ground (GND) of the DomBus network!

Using input ports to read temperatures

DomBus modules have the ability to read temperature by using NTC sensors with 10k resistance @25°C and B=3950 coefficient.
NTC should be connected to inputs that already have the internal 10k pullup resistor, otherwise an external 10k resistor must be applied. Connect NTC sensor between input and GND.

Setting IN_ANALOG,FUNCTION=3950 the module port is configured in analog mode, and DomBus driver will convert the read value to the temperature value in °C.

Application notes

Using DomBus12 to control two 230V devices, using the additiona module DomRelay2  (with 2 relays)

Just connect the two open-drain outputs to the 2-relays module by any type of cable (for example a standard 4x0.22mm²).

These outputs can be configured as OUT_DIGITAL or, better, as OUT_RELAY_LP: in this case the relay power consumption will be 1/3 or less.

Connecting Eastron SDM230 to DomBus12 to measure import and export energy/power on Domoticz, or DDS238-2 to measure imported power/energy

Many energy meters, like Eastron SDM230, provide 2 pulse outputs to count the import and export energy, 1 pulse every Wh (1000 pulses per kWh). More info in the Energy Meter page.

Using DomBus12, DomBus23 or DomBusTH it's very easy to read the pulses from energy meters, compute the instant power and get two devices in Domoticz that show the usage and return power, usage and return total energy and graphs. Below the instructions that refer to Eastron SDM230 energy meter: similar procedure for any other energy meter with pulse outputs.

1. connect the pulse outputs to any available I/O, for example IO8 and IO9 for DomBus12, IO1 and IO2 for DomBusTH or DomBus23.  The SDM230 common terminal block should be connected to GND (0V).
2. configure Pulse1 output, on SDM230, as EXP kWh (check the manual to know how to do that); Pulse2 is pre-configured as IMP kWh (measure the energy imported from grid)
3. configure the Domoticz device connected to Pulse2: press Edit on that device, and replace in the Description field IN_DIGITAL or IN_TWINBUTTON (the default value) with IN_COUNTER,TYPENAME=kWh  and save. Please note that kWh is CASE SENSITIVE!
   Now the device will be automatically moved to the Utility panel and configured as energy meter. Edit it again, write a name (for example PowerMeter_Import), and select Usage type.
4. if produced energy should be measured, configure the Domoticz device connected to Pulse1 as before: press Edit on that device, and replace in the Description field IN_DIGITAL or IN_TWINBUTTON with IN_COUNTER,TYPENAME=kWh and save.
   Now the device will be automatically moved to the Utility panel and configured as energy meter. Edit it again, write a name (for example PowerMeter_Export), and select Return type.
5. In case of both import and export devices are created, it's needed to specify on Import device the Unit number of the Export device, and vice versa. So, select Setup -> Devices and write down the Unit number corresponding to Import (for example 98), and Export device (for example 99), then go to Utility panel, edit Import device and add to the description ,OPPOSITE=99 (Unit of the Export device) and save; edit Export device and add to the description ,OPPOSITE=98 (Unit of the Import device) and save. In this way, when a pulse is received on Import device, the power on Export device will be immediately set to 0, and vice versa, when a pulse is received on Export device, the power on Import device will be set to 0.

In case that power should be measured in a single way (unidirectional), DDS238-2 can be used (it's cheaper than SDM230!) and it's S0 output (pulsed) should be connected to a DomBus module input. As DDS238-2 generates 2000 pulses/kWh, the DomBus device should be configured writing in the Description field IN_COUNTER,TYPENAME=kWh,DIVIDER=2000

Domoticz needs up to 5 minutes before updating the energy counter correctly.

Domoticz script the script_device_power

Installing the files script_device_power.lua  and config_power.lua provided on GitHub into the scripts/lua directory of Domoticz, it's possible to add the following functions to Domoticz:

1. power outage detect => turns on Leds (and other devices) in case of blackout (power failure)
2. import and export power displaying, through red/green leds on DomBusTH (red led flashes 1 time if import power <1kW, 2 times if <2kW, ... green led flashes 1 time if export power <1kW, 2 times if power < 2kW, ....)
3. in case of high power usage, program heat pump to work at lower level, or disconnect loads to prevent power disconnect. In case there are not any load that can be disconnect, send alert through leds/buzzer/siren, and send alert by Telegram
4. automatically enable loads in case of extra power from renewable sources, to increase the own-consuming: for example activate an electric heater if temperature is below a level and available power is greater than heater power

#from linux shell, type the following commands (copy and paste): lines starting with # are comments, and can be ignored
#become root
sudo su -
#enter domoticz directory /scripts/lua
cd ~pi/Domoticz/scripts/lua
if [ -d domoticz_lua_scripts ]; then
  cd domoticz_lua_scripts
  #update domoticz_lua_script local repository
  git pull
  cd ..
else
  which git
  if [ $? -ne 0 ]; then
    #install git
    apt install git
  fi
  #download domoticz_lua_scripts repository with all scripts
  git clone https://github.com/CreasolTech/domoticz_lua_scripts.git
fi
cp -i domoticz_lua_scripts/script_device_power.lua domoticz_lua_scripts/config_power.lua .
if [ ! -r globalvariables.lua ]; then cp domoticz_lua_scripts/globalvariables.lua . ; fi
if [ ! -r globalfunctions.lua ]; then cp domoticz_lua_scripts/globalfunctions.lua . ; fi
#now edit config file
nano config_power.lu

and adjust the information in the configuration file to match your home automation system.

Connecting a water meter or gas meter to Domoticz

Water and gas meter usually have an optoinsulated output that generate a pulse every 0.NNN m³.

Connecting that output to an I/O input of DomBus12, or DomBus23 or DomBusTH, and common output to GND, it's possible to get an incremental counter in Domoticz measuring water, gas, and anything else: counter divider, meter offset and unity of measure can be specified in Domoticz.

The I/O device connected to the meter should be configured in this way: click Edit on the domoticz device, write the appropriate name (for example Water_Meter), replace the current device type (e.g. IN_DIGITAL) in the Description field with IN_COUNTER and save: the device will be moved to the Utility panel and is ready to count pulses.

Using DomBus12 module to control 2x 230V loads by using 2 buttons, 4 magnetic contact sensors and 1 PIR

The following schema shows how to use this home automation module to control some alarm sensors (PIR, to detect movements inside a room, and 4 magnetic contact sensors applied to windows, doors and blinds, to detect the open state and transition), and also command 2 loads (light and dehumidifier, for example) by using the additional DomRelay2 board (within 2 relays) placed near the loads and connected to DomBus12 by a small wire cable.

Both DomBus12 and DomRelay2 are very small modules that can fit everywhere.

The two buttons are connected together by a 4k7 resistor and connected to a single input wire: this configuration is called "twinbutton" and permits to use 2 buttons for each module input, and is normally used by double buttons with the function UP/DOWN (applied to roller shutters, for example) or ON/OFF.

DomBus12, DomBus23, DomBus31 and DomBusTH have also the possibility to send command directly to other devices of the same family (and also to itsself), with the following gains:

1. very easy configuration (don't need to configure the controller); for example it's possible to configure a button to activate a load, writing the command on the device description like shown below
2. up to 8 commands are supported for each input/sensor
3. these commands are received and managed by DomBus modules without any latency introduced by the controller
4. commands work also in the case that the controller is down

Example: module address = 1201, with 2 buttons connected to port 1 and configured as IN_TWINBUTTON, with the following functions:

Short pulse on DOWN button to get light (connected to port 6 of module 1201) ON for 120s: DCMD(Pulse)=1201.6:ON:120s

2s pulse on DOWN button to toggle the same light ON/OFF without any timer: DCMD(Pulse2)=1201.6:TOGGLE

Short pulse on UP button to swith the dehumidifier (connected to port 5 of module 1201) ON for 2 hours: DCMD(Pulse)=1201.5:ON:2h

1s pulse to switch dehumidifer OFF: DCMD(Pulse1)=1201.5:OFF

To configure the port 1 of module 1201 in this way it's sufficient to edit the port 1 device in Domoticz, and write in the description all commands above:

IN_TWINBUTTON,DCMD(Pulse)=1201.6:ON:120s,DCMD(Pulse2)=1201.6:TOGGLE,DCMD(Pulse)=1201.5:ON:2h,DCMD(Pulse1)=1201.5:OFF

Then light and dehumidifier will work even if Domoticz is offline.

DomBus12 connected to one or more temperature sensors, in a greenhouse

DomBus12, as like as other DomBus modules with analog inputs and 10k pullup resistors, can be connected to NTC thermistors to measure temperature, using NTC 10k 3950 type sensor that are very common and cheap. Also, they are available in sealed/waterproof version, with 2 wires cable that can be extended for 50-100m distance using common alarm cable 2x0.22mm² + shield; using a single 4x0.22mm²+shield cable it's possible to connect 4 different temperature sensors.

The diagram below shows DomBus12 module with 4 temperature sensors connected on IO1-4, a remote double relay module DomRelay2 connected to IO5-6, and 2 pushbuttons to IO8-9.
I/O device connected to the NTC temperature sensor should be configured, in Domoticz, as IN_ANALOG,FUNCTION=3950 and also it's possible to add an offset to compensate any temperature error, for example IN_ANALOG,FUNCTION=3950,B=0.2 if the real temperature is 0.2°C over the measured temperature.

Connecting DomBus12 to 9 NTC thermistors

DomBus12 has 4 inputs that can be configured as IN_DIGITAL,FUNCTION=3950 and connected to NTC thermistors, 10k @25°C with 3950 constant: in this way it's possible to measure up to 4 fluid or air temperatures.
If more NTC sensors should be connected, it's possible to do an hardware modification to get up to 9 NTC temperature sensors connected:

1. a wire should be soldered to the pad indicated by the red arrow, to carry 3.3V outside
2. connect 10k 3950 NTC thermistor between IOx and GND, and a 10k resistor between IOx and 3.3V wire, where x=7-9
3. if 7 NTC thermistors are not sufficient, open ROx PCB jumpers, short RIx PCB jumpers by a soldering a tin ball, and connect 10k 3950 NTC thermistor between IOx and GND, and a 10k resistor between IOx and 3.3V wire, where x=5-6

Hardware ChangeLog

Firmware ChangeLoga

DomBus modules installation block chart

• Use a 12V power supply unit with backup battery charger, to avoid trouble on RaspberryPI or other devices. Also, in this way it's possible to get everything working even in case of power outage (domotic controller, domotic modules, network switches, routers, NVR and IPcams).
• Use a 12V lead-acid battery well dimensioned to supply everything during blackout.
• Use a DC/DC converter 12V → 5V 3A to supply the RaspberryPI, if you have it.
• To use DomBus modules, use a standard alarm shielded cable (within 4 wires) to interconnect all modules to RaspberryPI (through a cheap RS485 to USB adapter).
• Protect each bus with a fuse

Ports parameters

DCMD commands

This is an experimental function, undergoing testing and development, available on all DomBus modules, expept DomBus1

For each port it's possible to configure, through the Domoticz Description field, one or more DCMD commands.

DCMD is a command that is sent to the module itself or to another DomBus module, in response to an event, and more DCMD commands can be specified for the same event and port.

Also it's possible to send DCMD command to the domotica controller to activate, deactivate or toggle a scene/group; to get this feature please assure that:

• 127.0.0.1 was added to Domoticz → Setup → Settings → Trusted Networks field
• if Domoticz www port is different from 8080, manually replace 8080 with the used port in the plugins/CreasolDomBus/CreasolDomBusProtocol.py file:
  JSONURL = "http://127.0.0.1:8080/json.htm"

The syntax is DCMD(Event:ValueLow:ValueHigh)=ModuleAddress.ModulePort:Command:Value

where ValueLow, ValueHigh, Value are optional parameters.
When ModuleAddress corresponds to the same module that we're editing, the command is executed locally, by the same module.
When ModuleAddress corresponds to another Dombus module, the command is sent by bus to that module. When ModuleAddress is 0, the command is sent to the controller to activate the scene/group with idx=ModulePort : please note that ModulePort should be in hex format, so if ModulePort=11 the scene/group with idx=17 will be activated.

Example 1: configure a pushbutton switch to have 3 functions

IN_DIGITAL,INVERTED,
DCMD(Pulse)=0101.1:TOGGLE,
DCMD(Pulse1)=0101.2:ON:30m,
DCMD(Pulse2)=0101.2:OFF

Example 2: configure a pushbutton switch to trigger 2 scenes/groups

IN_DIGITAL,INVERTED,
DCMD(Pulse)=0.1:Toggle,
DCMD(Pulse2)=0.2:On

Example 3: temperature sensor that enable/disable electric heater and valve

In the description field of the temperature sensor we'll write

DCMD(Value:0:20.5)=0101.3:ON, (if temperature between 0 and 20.5°C, turns ON heater on output 3 of module 0x0101)
DCMD(Value:0:20.5)=0102.1:ON, (if temperature between 0 and 20.5°C, turns ON valve output 1 of module 0x0102)
DCMD(Value:20.8:50)=0101.3:OFF (turn OFF heater when temperature above 20.8°C)
DCMD(Value:20.8:50)=0102.1:OFF (turn OFF valve when temperature above 20.8°C)
Domoticz temperature sensor Description will be:

TEMPERATURE,
DCMD(Value:0:20.5)=0101.3:ON,
DCMD(Value:0:20.5)=0102.1:ON,
DCMD(Value:20.8:50)=0101.3:OFF,
DCMD(Value:20.8:50)=0102.1:OFF

Installation

Using RS485 specific cables it's possible to get almost 1km linear bus with several devices attached. Alternatively, it's possible to use 2 twisted pairs of cheap Cat6 UTP or STP cable, one twisted pair for data (A and B) and one for 12-24V power supply. Ideally, all devices should be connected using a linear bus topology, to get the lowest reflection/noise, and connect 100-150 Ohm resistor on the two ends, as illustrated in the Fig. 2. In practice, this is not important for common buildings.

At Raspberry/PC side, it's possible to use a cheap USB-RS485 adapter, if a serial port with RS485 driver is not already available.

Using DomBus modules it's possible to:

1. avoid RF pollution
2. no need to periodically change batteries on sensors/actuators
3. using a UPS or  13.6V power supply with backup battery, it's possible to get a building automation system that works also in case of power outage
4. very very low power consumption

Writing a microSD card with a fresh Raspbian + Domoticz distribution

Click here if you need to write a microSD card with a clean updated Raspbian+Domoticz image optimized to extend SD life (minimizing writings), and with some addons (firewall, backup, libraries).

Adding DomBus plugin to Domoticz

Linux version

This procedure is not needed in case of a new Domoticz installation writing the SD as written above.
If Domoticz does not already include the DomBus plugin, type the following commands (from Linux root shell: type sudo su - to become root):

#install git, if not already installed
which git
if [ $? -ne 0 ]; then sudo apt install git; fi

#change to the domoticz directory / plugins
cd /home/pi/domoticz/plugins 

#fetch the Python Plugin Manager (that can be used to install/upgrade other plugins, including Creasol DomBus)
git clone https://github.com/ycahome/pp-manager

#fetch Creasol Plugin
git clone https://github.com/CreasolTech/CreasolDomBus

#restart Domoticz daemon
service domoticz restart

Windows version

Domoticz configuration

After plugins installation and Domoticz restart, it's possible to add the Creasol DomBus hardware (Setup->Hardware , add new "dombus" hardware type "Creasol DomBus" and specify the serial device, normally /dev/ttyUSB0) and connect the DomBus device to the RS485 bus.
DomBus module is factory programmed with a default address indicated above, and only one port will be automatically added to the Switches panel of Domoticz. Enter the Switches panel, find the new device with the DomBus default address, click on Edit and add in the description ,HWADDR=0x0001 to set the new address to 0001, or specify another address of your choice. Reload the Switches panel to see all input/output/led ports of DomBusTH active.

With Domoticz, each DomBus port can be configured via the Domoticz device description: for example a port IN_DIGITAL normally is On when it's left unconnected, and Off when it's shorted to GND, but it's possible to invert this function specifying in the device description the parameter INVERTED, separated by a comma (,): IN_DIGITAL,INVERTED . Relay outputs can be configured writing in the description field OUT_DIGITAL or OUT_RELAY_LP: in the latter case, relay are internally managed to assure a low power consumption.
Please check the sections Ports capabilities and Ports parameters.

Ports that are not used can be disabled in Domoticz Setup → Devices clicking on the blue arrow of each useless port (device), but in case of a bus with almost 255 ports, it's suggested to disable the unused ports by using the DISABLE command:
1. suppose that DomBus module 0x0001 has ports 3,4,5,6,8 not used
2. in Domoticz Switches panel select port1 of that module ([0001.1] RL1)
3. click on Edit, and add in the Description field DISABLE=3:4:5:6:8 and click on Save.
In this way, the selected ports will be disabled and removed from the Devices list. With this solution it's possible to add more DomBus modules to the same bus, with up to 255 enabled ports. In large buildings, it's a good practice to have more than one bus, to divide floors or areas.

Updating DomBus plugin on Domoticz

1. Go to Setup → Hardware → PP-Manager (name of the python plugin manager)
2. Assure the PP-Manager is enabled
3. Pluging to install: select Creasol DomBus
4. Auto Update: choose Selected
5. Click on Update button

Linux platform, with DomBus plugin installed manually

cd DOMOTICZ_HOME/plugins (e.g. cd /home/pi/domoticz/plugins)
git clone https://github.com/CreasolTech/CreasolDomBus.git

Linux platform, with DomBus plugin installed using git

cd DOMOTICZ_HOME/plugins/creasolDomBus (e.g. cd /home/pi/domoticz/plugins/CreasolDomBus)
git pull

Windows platform

Files should be downloaded from the github repository https://github.com/CreasolTech/CreasolDomBus by using git program or www browser, then placed in the DOMOTICZ_HOME/plugin/CreasolDomBus directory

Installing CreasolDomBus Home Assistant custom component

cd /tmp
git clone https://github.com/CreasolTech/home-assistant-creasol-dombus.git
cp -a home-assistant-creasol-dombus/custom_components HADIR/config/
ha core restart

FAQ about DomBus products

• Some modules are available with both DomBus and Modbus protocol firmwares, so the best one for your needs should be chosen. Below in the FAQ some information about the two protocols
• You can connect up to 20-30 modules per bus: the max number of ports managed by Domoticz is 256, and you can use the DISABLE command to disable ports that are not used in case that 256 ports are not enough.
• It's good to make different buses on large buildings with several sensors and actuators, for example a bus for the ground floor, one for the second floor, ... Any bus is connected to a RS485 port/adaptor and need a DomBus plugin for that serial port, so in the Domoticz Setup→Hardware, one Creasol DomBus line for each serial port.
• DomBus modules are factory programmed with a certain address, for example 0xff12 for DomBus12, 0xff23 for DomBus23, and so on. As each device connected to the bus MUST have a unique address, add only one module to the bus then program its address using the command HWADDR=0x0001, then connect another DomBus module and program its address to 0x0002 and so on. Address can be chosen to identify floor and room, for example 0x1023 to identify floor 1, room 2, module 3 in that room.

How can I change address of DomBusTH device?

DomBusTH: how to mount and fix it?

DomBusTH: how to do a factory reset?

Why buzzer does not work?

2 or more modules with the same address

How many DomBus modules can I connect to a bus?

How to split a bus in 2 buses in Domoticz?

How to identify a RS485/USB adapter when more than one are connected

All DomBus devices have been duplicated!

I have many USB-serial adapters

Why there is a long delay between pushing a button and get light/output on?

Why DomBus device does not work?

One DomBus module stopped working

Why current consumption is 0uA?

How to add icons on smartphone to turn On/Off lights/loads, or enable/disable scenes/groups?

How to send Telegram notification from a lua script in Domoticz?

-- script_time_example.lua  : simple example script that write a message to Telegram channel/group if temperature is less than 5
commandArray={}
dofile "script/lua/globalvariables.lua" -- read a file with some variables, including Telegram API key and ChatID
dofile "script/lua/globalfunctions.lua" -- read a file with some functions
if (tonumber(otherdevices['Temp_outdoor']) < 5) then
	telegramNotify("Low temperature: bring flowers inside")	-- send message by Telegram
end
return commandArray

2022-11-04 Rev02g4

2022-10-22 Rev02g3

2022-09-26 Rev02g

2022-02-07

2021-12-02

2021-10-25

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2021-03-16

2020-12-28

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