To add a 2-wire (I2C) temperature or environmental sensor, you should select any pin, select the “Temperature (2-wire)” sensor type, and select a subtype (e.g., BMx280), specify the I2C address of the sensor as a decimal number. On the next row (Output2 in this example), you should define a I2C clock pin.
First of all, you must specify a pin for a sensor. It is the SDA pin. Then it would help if you defined the SCL pin. For example, output 4 – BME280, and output 5 – I2C SCL.
If you connect several sensors on one bus (pin), you may define the SCL pin only once.
Zigbee: Accepts the “read” and “write” commands on the endpoint for the SDA pin.
When building your own DIY Zigbee devices, incorporating a display can significantly enhance their functionality and user experience. From simple 7-segment LED indicators to more advanced LCD or OLED screens, displays provide a practical and visually appealing way to interact with your Zigbee device. This article will explore the various types of displays you can use, their compatibility with Zigbee-based projects, and tips for integrating them seamlessly into your DIY designs.
The SGP40 is a digital gas sensor designed for indoor air quality monitoring by measuring volatile organic compounds (VOCs). Key features include long-term stability, low-power consumption, and an I²C interface for easy integration with microcontrollers.
⚠️ THIS FEATURE IS AVAILABLE ON CC2652 or CC1352 CHIPS ONLY
⚠️ THIS FEATURE REQUIRES THE PREMIUM VERSION
The SGP40 sensor (Buy on AliExpress #1, #2) requires environmental temperature and humidity for better results. The example above shows that two I2C sensors are connected on the same bus. SHT30 provides the necessary data. It should be defined first in the configuration (above) in the configuration. You could also use separate sensors for temperature and humidity in the same manner.
The firmware converts the raw value from the sensors to the VOC index value in the range from 0 to 400 and reports it as an analog value.
| 0-100 | Excellent | No measures needed |
| 100-200 | Good | No measures needed |
| 200-300 | Lightly Polluted | Ventilation suggested |
| 300-400 | Moderately Polluted | Increase ventilation with clean air |
| 400-500 | Heavily Polluted | Optimize ventilation |
A home automation system can also send temperature and humidity instead of built-in sensors. You should send it as a single precision float in the analog input value cluster.
Analog value: 65NNN where NNN is a humidity value, for example, 65050 for 50%. Humidity range: 0 … 100.
Analog value: 64NNN where NNN is a temperature value, shifted by 25. For example, 64000 for -25C, 64025 for 0C, 64050 for 25C. Temperature range: -25 … 100.
Ownerwrite - set the temperature value 25C.
Topic: zigbee2mqtt/[friedly_name]/set
Payload: {"[channel]": 64050}
Channel: l1, l2, l3 … l16
write - set the humidity value 50%.
Topic: zigbee2mqtt/[friedly_name]/set
Payload: {"[channel]": 65050}
Channel: l1, l2, l3 … l16
The INA226 is a high-side current shunt and power monitor with an I2C interface. These sensors offer high accuracy for current and voltage measurements in various applications. With its integrated ADC, the INA226 can measure bus voltages from 0V to 36V and shunt voltages with a common-mode voltage range. It provides programmable conversion times and averaging, making it versatile for different precision requirements.
The INA219 is a simpler device suitable for basic current sensing applications, while the INA226 offers higher precision and additional features such as integrated voltage reference and programmable alert functions. The INA226 is ideal for more demanding applications that require precise current measurement and advanced monitoring capabilities.
INA3221 offers a 3-channel monitoring module.
INA sensors are I2C-compatible and commonly used in power management systems, battery chargers, and various industrial applications where accurate current and voltage measurements are essential for monitoring and control purposes.
INA219 resolution – this option allows you to select a measurement voltage and current range (wider range – less accuracy).
INA226 resolution – this option depends on a used shunt resistor with your sensor or sensor board (less current – higher accuracy). Please note that the firmware does not support other nominal values for shunt resistors.
The X9C102, X9C103, X9C104, X9C503 are digitally controlled (XDCP) potentiometers. The device consists of a resistor array, wiper switches, a control section, and nonvolatile memory. The wiper position is controlled by a three-wire interface.
⚠️ THIS FEATURE IS AVAILABLE ON CC2652 or CC1352 CHIPS ONLY
From X9C10X to a Zigbee module:
GND: connected to GND on a Zigbee module.
CS (chip select): Connected to any pin configured as X9C100 (P00 – DIO0, see below).
INC (increment): Connected to any pin configured as I2C SCL/SPI CLK (e.g., P02 – DIO2).
U/D (up/down): : Connected to any pin configured as an additional parameter (e.g., P04 – DIO4).
VCC: Connected to 3.3V.
Remember state – if this option is active, the firmware remembers the last level and restores it after power up. Otherwise, the firmware sets the maximum resistance on the X9C10X output (VL – VW).
Pin (Up/Down) – it is the “U/D” pin. It has the same pull-up resistor settings as the master output pin.
Transition time (ms) – if this interval is not zero, the firmware smoothly changes the output resistance between two states.
Linked input – the mode of the linked input that controls this output.
The device acts as a level control device. You can change the level from 0 to 255, and the firmware scales it to 0 – 99 levels in X9C10X. When you set the zero level in Zigbee, the firmware forcibly makes 99 steps down. It allows synchronizing levels between the device and Zigbee. In other cases, the firmware calculates a difference and makes the necessary number of steps up or down.
Zigbee cluster: ZCL_CLUSTER_ID_GEN_LEVEL_CONTROL
Zigbee attributes: ATTRID_LEVEL_CURRENT_LEVEL (uint8)
Zigbee commands: read, write, moveToLevel, moveToLevelWithOff
on/off - The "Off" command sets the minimum level, and the "On" command restores the last level (before off). Look for commands and examples for GPIO outputs.
write - sets the level. Topic: zigbee2mqtt/[friedly_name]/[channel]/set/brightness Channel: l1, l2, l3 … l16 Payload: value (0 - 255)
Topic: zigbee2mqtt/[friedly_name]/set/[channel]
Channel: l1, l2, l3 … l16
Payload: {"brightness": value, "transition": 3}
value - 0 - 255.
transition - (optional) the transition time in seconds between states.
read - reads the current value
Topic: zigbee2mqtt/[friedly_name]/[channel]/get/brightness
Payload: none
Returns: {"brightness_[channel]": value}
The HX711 Load Cell Amplifier is a module that is used to take the signal coming from your load cell and convert it into a digital signal that your Zigbee-compatible chip can take and process.
⚠️ THIS FEATURE IS AVAILABLE ON CC2652 or CC1352 CHIPS ONLY
From Load Cell to HX711:
Red wire: E+ on HX711
White wire: A-
Black wire: E-
Green wire: A+
From HX711 to a Zigbee module:
GND: connected to GND on a Zigbee module.
DT (data): Connected to any pin configured as HX711 (P00 – DIO0, see below).
SCK: Connected to any pin configured as I2C SCL/SPI CLK (e.g., P02 – DIO2).
VCC: Connected to 3.3V.
Scale factor – allows you to convert a raw sensor’s value to a weight value.
Shift – allows you to calibrate a zero offset (tare weight).
Zigbee cluster: ZCL_CLUSTER_ID_GEN_ANALOG_INPUT_BASIC
Zigbee attributes: ATTRID_IOV_BASIC_PRESENT_VALUE (single precision float)
Zigbee commands: write
on/off - Enables the zero calibration process (tare). Look for commands and examples for GPIO outputs.
write - sets the PWM duty cycle. Topic: zigbee2mqtt/[friedly_name]/[channel]/set/brightness Channel: l1, l2, l3 … l16 Payload: value (1-99999999, scale factor)
The SCD40 is a compact CO2 sensor that provides accurate carbon dioxide (CO2) measurements along with temperature and relative humidity readings. Key features include its small form factor, low-power consumption. It I2C- compatible sensor where you should configure the SDA and SCL pins, and define the sensor I2C address (see an example below). Of course, you can have different pins in your setup.
If your device is configured for power saving, the sensor measures all values only once when the firmware sends a periodic report. Please note, that every measurement takes about 6 seconds.
Otherwise, the sensor measures all values periodically every 5 seconds, but the firmware sends measured values with periodic reports.
⚠️ THIS FEATURE IS AVAILABLE ON CC2652 or CC1352 CHIPS ONLY
Altitude – altitude over a sea level of your location for precise results.
Auto-calibration – the sensor will self-calibrate every several hours if you enabled this option.
You may send some sensor-specific commands to your higher-level system. You should write the necessary command single precision value to the “Analog input” cluster.
63000 – factory reset.
63001 – sensor restart (re-init).
63002 – start self testing. It takes about 10 seconds.
63900 – 64100 – set a temperature offset (64000 + offset value, so, the offset can be positive or negative). By default, the sensor has the temperature offset of 4 °C. If you see that the sensor measures a wrong temperature value, you can change this offset (note, this is an environment’s temperature).
65000 – 66100 – set the ambient pressure in kPa (65000 + pressure value). The maximum pressure value is 1100 kPa.
write - Zigbee write command.
Topic: zigbee2mqtt/[friedly_name]/set
Payload: {"[channel]": 63002}
Channel: l1, l2, l3 … l16
The firmware supports the most popular RTC chips like DS3231 and DS1307. These battery-powered chips can count time independently with the main module. The firmware reads the time from these chips at the boot time and periodically synchronizes the module’s time with RTC.
RTC chips support the I2C protocol. Therefore, you can add them in a similar way, like other I2C sensors.
⚠️ THIS FEATURE IS AVAILABLE IN THE PREMIUM VERSION
⚠️ THIS FEATURE IS NOT AVAILABLE IN THE CC2530/CC2531 ROUTER FIRMWARE
Zigbee cluster: ZCL_CLUSTER_ID_GEN_TIME
Zigbee attributes: ATTRID_TIME_TIME (UTC data type, 32-bit number of seconds since Jan 1, 2000)
Zigbee commands: read, write.
You should create a custom converter for your device, place it in the “data” folder, and add it to the configuration.
read - immediately reads the current time.
Topic: zigbee2mqtt/[friedly_name]/get/[channel]
Channel: l1, l2, l3 … l16
Payload: 1
Returns: The counter value {"[channel]": float_value}
write - this command allows you to synchronize time with the host. It is not recommended to call it directly because the device expects an encoded value. The custom converter gets the current host's time and calculates the correct value automatically.
Command example:
const values = {timeStatus: 3, time: time};
endpoint.write('genTime', values);
A rotary encoder is a type of position sensor used to determine the angular position of a rotating shaft. It generates an electrical signal, either analog or digital, according to the rotational movement (more info).
The firmware counts impulses in the 500 ms interval and sends a positive value for CW rotations and a negative value for CCW rotations. Optionally, the firmware can handle and send an event for a click button.
Output 2 → S1
Output 3 → S2
Input 1 → Key
GND → GND
3.3V → VCC
The image above is an example. You can connect “Output 1” and “Output 2” signals to any available pins. The “I2C SCL” line should be defined immediately after the “Rotary encoder” sensor.
Note: Output and input pins are not relevant for sensors. You can also configure your rotary in input pins, but without additional options.
Changes level – this option allows you to link the rotary encoder to a PWM or LED output and control PWM signal width or brightness level up or down.
Sensitivity – this option is used when with the previous option and changes a step size per each tick.
If your encoder has the additional push button, you can connect it to an input, and it will toggle a linked output state.