Video showing Creasol DomBus modules in brief

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/CreasolDomBusGateway.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

Example 4: configuring touch sensor of DomBusTH to activate Domoticz scenes/groups with a buzzer feedback

A piezo buzzer (without oscillator) should be connected to IN3 and IN4, and IN3 should be configured as OUT_BUZZER.

Toggle ON/OFF group with idx=17 (0x11 in hex) with a short pulse, less than 0.5s: DCMD(Pulse)=0.11:Toggle

Create a short 500ms buzzer feedback...module address is 5101 and IN3 port is 5: DCMD(Pulse)=5101.5:On:2 where 2=2*250ms and can be increased up to 9*250ms. Then, specifying 10, 20, 30, and other multiple of 10, instead of emitting a short or long beep the buzzer produces N beeps. For example, if value is 20, 2 beeps are emitted, followed by 4s of pause, then other 2 beeps and so on.

Activate the scene with idx=16 (0x10 in hex) when the touch sensor is ON for 2s: DCMD(Pulse2)=0.10:On

In this case, also transmits a long buzzer alert, 1.5s: DCMD(Pulse2)=5101.5:On:6

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, or a common shielded alarm cable with 4 wires, 2x0.22mm² for data and 2x0.50mm² for 12-24V power supply: alarm cable is cheap and thin, very easy to route.
Ideally, all modules 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: RS485 is a industrial grade very strong balanced bus!

In case that a cable cannot be routed, find here more info about wireless connection to a DomBus module or a network of DomBus modules!

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

Using DomBusGateway to manage DomBus network and communicate by MQTT AutoDiscovery with Home Assistant, OpenHAB, ioBroker, Node-RED, ...

Using DomBus modules with Modbus firmware

• Some DomBus I/Os are versatile and can be used as input or output, with 10k pullup or not. For this reason, some modules provide PCB jumpers to enable/disable pullup, enable/disable low impedance output, transform input to output and vice-versa. PCB jumpers identified by the text ROn (where n is the corresponding I/O number) permits to enable/disable a low impedance resistor to use the IOn port as output or input; RUn identifies jumper that enable/disable the 10k pullup for IOn. Before using the module it's better to plan how I/Os should be configured, acting on the corresponding PCB jumpers, if available.
  Twinbuttons, sensors_alarm, NTC 10k thermistors need that the 10k pullup resistor is enabled!
• RS485 bus uses a balanced twisted pair to communicate over long distances (200m, at 115200bps), but the bus must be terminated by two 100÷150 Ohm resistors, one on each bus end. DomBus modules usually have a resistor that can be enabled by a PCB jumper: use a common solder iron to make a tin ball on that jumper to enable it.
  The RS485 bus can be connected to the domotic controller by a cheap RS485/USB adapter or by a RS485/NET module (WiFi or Ethernet): more info on wireless connection to a DomBus module or network here!
• Each DomBus module type have a default address, for example DomBus37 has modbus address 0x37 (55) and DomBusEVSE has address 0xe3 (227): to use more than one module in the same bus, each module must have a unique address. To configure the address, speed/parity (if needed), and also to configure each port type and option, and other parameters, it's possible to use any modbus program. For Linux users, mbpoll is perfect:
  mbpoll -b115200 -Pnone -mrtu -a55 -0 -1 -r8192 /dev/ttyUSB0 1 to configure address of a DomBus37 (default address = 55) to the value 1.
  mbpoll -b115200 -Pnone -mrtu -a1 -0 -1 -r256 /dev/ttyUSB0 17 17 17 17 9 8 to configure ports 1÷4 as SENSOR_ALARM (balanced double or triple biased alarm sensors), port5 as TWINBUTTON (up/down button connected to a single port using a 10k resistor) and port6 in ANALOG mode to read an external voltage or a temperature sensor.
  mbpoll -b115200 -Pnone -mrtu -a1 -0 -1 -r529 /dev/ttyUSB0 1 to set INVERTED flag for port 18 (512+18-1=529), getting relay operating as normally-closed.
  
• To configure the domotic software, please check the GitHub examples for Home Assistant, Node-RED.
  If you intend to use the module with other software, or you want to share your configuration, please contact us by Email or Telegram. Thanks a lot!>

FAQ about DomBus products

• DomBus 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 connected to the main controller by a simple USB/RS485 adapter.
• 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 or WiFi/LAN/RS485 module.
• 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 just one module to the bus then program its address to a unique number from 1 to 0xefff 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.
• On Domoticz the max number of managed ports is 255, and you can use the DISABLE command to disable ports that are not used in case that 255 ports are not enough.
  Install the CreasolDomBus plugin (available on Python Plugin Manager: see section above).
  Connect a DomBus module to the RS485 bus and check on the Switching panel: you'll find a new device in the last position.
  Click on Edit and add ,HWADDR=0x0001 to set the new hardware address for the module (address must be unique!): reload the Switches/Temperature/Utility panels and you'll find new devices corresponding to each module port.
  Each device (module port) can be configured by using the Description field, so you don't need to any web UI to configure it, and in case that a module will be damaged, just replace with a new module, connect it to the bus, program it with the same hardware address, then for each port click on Edit button and Save button to restore previous configuration.
  
• For Home Assistant, OpenHAB, NodeRED, ioBroker, ... it's possible to use the DomBusGateway python software that translates DomBus protocol to MQTT with AutoDiscovery, and vice-versa.

How can I change address of DomBusTH device?

DomBusTH: how to mount and fix it?

DomBusTH: temperature and humidity sensor stopped updating

DomBusTH: how to do a factory reset?

Why buzzer does not work?

2 or more modules with the same address

How to use a RS485/NET or ModbusTCP gateway, or a radio link between DomBus and the domotic controller?

Check the page about Modbus TCP - RS485/Net gateway and radio link between two RS485 networks.

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?

DomBusEVSE does not work - Checklist

DomBusEVSE and DomBus34: 2 energy meters with same Modbus address

DomBusEVSE: when charging sessions starts and stops?

DomBusEVSE: I don't want that charging starts as soon as the vehicle is plugged

DomBusEVSE: how to simulate that a vehicle is plugged, asking for charging or notifing an error?

DomBusEVSE: is it possible to read battery State-of-Charge from the vehicle?

SENSOR_ALARM: how to manage balanced double-biased and triple-biased alarm sensors with DomBus module

DomBus devices support, on input ports with 10k pullup resistor, connection to alarm sensors that have multiple states, for example magnetic contact sensors, PIRs and other motion sensors, that with a single wire provide the states Closed, Open, Masked (zone disabled), Tamper (wire disconnected), Shorted (wire shorted): of course it also supports sensors that do not manage the Masked state (disabled zone).
DomBus is a really versatile module because permits to manage any kind of this sensors by specifying, for each input, the voltage thresholds (in range from 0 to 65535) to determine each state, so it's possible to realize a complete burglar alarm system using DomBus modules with a home automation software like Domoticz, Home Assistant, OpenHAB, ...
The following table shows the thresholds (PAR1, PAR2, PAR3, PAR4) for some common sensor types.

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

DomBus firmware ChangeLog

2025-02-05 02j5

2024-12-01 02j3

2024-07-10 02j2

2024-05-15 02j1

2024-03-29 02i9

2024-02-29 02i7

2023-11-28

2023-07-15 Rev02i2

2023-06-13 Rev02h4

2023-04-07 Rev02h3

        0   ⇒ OFF
        1   ⇒ solid ON 
        2   ⇒ ON for 250ms 
        3   ⇒ ON for 500ms 
        4   ⇒ ON for 750ms ...
        9   ⇒ ON for 2000ms
        10  ⇒ 1 beep/flash followed by 2s pause, forever
        11  ⇒ 1 beep/flash followed by 2s pause, only once
        12  ⇒ 1 beep/flash followed by 2s pause, only twice
        13  ⇒ 1 beep/flash followed by 2s pause, 3 times ...
        19  ⇒ 1 beep/flash followed by 2s pause, 9 times
        20  ⇒ 2 beeps/flashes followed by 2s pause, forever
        21  ⇒ 2 beeps/flashes followed by 2s pause, only once
        22  ⇒ 2 beeps/flashes followed by 2s pause, only twice
        and so on...

2023-03-07 Rev02h2

        in Italy, if contractual power is 6kW, it's possible to drain 6kW+27% for max 90 minutes, then power must decrease below 6kW+10% for at least 90 minutes
        MaxPower2 (e.g. 7600 Watt)                      ####################                    #########
        MaxPower  (e.g. 6600 Watt)  #####################################################################
                                    ^                   ^                   ^                   ^
        Time                        start               MaxPowerTime        MaxPower2Time       MaxPowerTime

2022-11-16 Rev02g5

2022-11-04 Rev02g4

2022-10-22 Rev02g3

2022-09-26 Rev02g

2022-02-07

2021-12-02

2021-10-25

2021-10-19

2021-03-16

2020-12-28

Need help? join the DomBus channel on Telegram!
Esiste anche il Canale Telegram in Italiano DomBus_it!