SmartRFy Sensor Module (HCMODU0141)

Hobby Components range of SmartRFy wireless RF products *** NEW ***
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SmartRFy Sensor Module (HCMODU0141)

Post by admin » Sun Feb 23, 2020 1:14 pm



Current progress......

1) Hardware design....................Done!
2) Firmware development......Done!
3) Testing.........................................In progress
4) Documentation
5) Initial production batch

The SmartRFy sensor module adds the option to interface to a standard DHT22 temperature and humidity sensor (see item HCSENS0002), a PIR sensor such as the very common HC-SR501 (see item HCMODU0003), and a light dependant photo-resistor (LDR) sensor (see item HCSENS0019), therefore adding the ability to remotely monitor temperature, humidity, light and motion via the SmartRFy network.

With the attached DHT22 and LDR sensor the module will, by default, transmit readings from these sensors once every 60 seconds (when reconfigured via the modules serial port this can be changed from 10 to 65535 seconds).
With an attached PIR sensor the module will transmit the state of the PIR whenever it detects a change in its state. The transmitted sensor state may then be used by any suitable configured remote SmartRFy module capable of receiving its data.

Besides the DHT22, LDR, and PIR sensors, the sensor module includes an auxiliary digital output which be assigned to any of the attached sensors (defaults to PIR and requires reprogramming via serial interface).



• Local and remote control via simple text based serial commands.
• Up to 255 zones and 255 addresses (default zone 0, address 0).
• Basic automation features (requires a USB to serial adaptor or microcontroller for configuration).
• Compatible with most microcontrollers featuring a serial UART interface.
• Wireless serial communication with 8 different baud rates (9600 default).
• Full two-way wireless communication - can both transmit and receive serial commands.
• Automatically read and transmit temperature and humidity readings from a DHT22 temperature sensor (will transmit readings once every 60 seconds by default).
• Automatically read and transmit light level readings from a light dependant resistor (will transmit readings once every 60 seconds by default).
• Can automatically transmit state changes from a connected PIR sensor.
• Built in auxiliary digital output. This output can be assigned to any of the attached sensors.


Product code: HCMODU0141
Supply voltage: 4.5 to 5.5V
Supply current min: 26mA (idle)
Supply current max: 117.5mA (transmit + relay energised)
Operating frequency: 433MHz (OOK)
Operating range: 30 Meters (unobstructed)
Interfaces: RF Tx and Rx, serial UART, DHT22, PIR, LDR, and relay
Aux output sink current: 100mA max.
Module dimensions (WxDxH): TBA

SmartRFy system overview

SmartRFy modules are a range of wireless modules that provide a simple low cost way of controlling and monitoring remote devices and sensors. They are designed to work at their basic level with no programming required. However, when reconfigured or controlled via their serial interface they can also provide more complex and even autonomous functions.
SmartRFy modules work by wirelessly communicating with one another using simple text based commands - for example, to turn on a remote relay a command such as RLY=1 can be sent, and to turn it back off RLY=0. These commands can be automatically sent from one module to another or can be sent by a user via a modules serial interface to manually control modules on the SmartRFy network.

They are addressable and can grouped into one of 255 zones, with each zone capable of individually addressing 255 devices, giving a total of over 65,000 unique addresses. SmartRFy modules are designed to be both easy and flexible to use by providing three levels of control:

Zero configuration (out-of-the-box)


With no configuration at all the SmartRFy range of modules allow basic functionality such as remotely switching relays, digital pins, or monitoring sensors, such as temperature, humidity, light, motion etc. All SmartRFy modules default to the same zone and address and so can respond to, or control, other modules without the need to modify any zone or address settings.

Serial port configuration


All smartRFy modules include a serial port which allows them to be re-configured using simple text based commands. These text commands allow changing of configuration settings and control of specific features of each module. Any setting changes are stored by the modules non-volatile memory and so are retained even when power is removed from the module. When reconfigured they are able to perform more complex functions and even some basic autonomous tasks. For example, a SmartRFy relay module can be reconfigured to control a heating system based on the temperature transmitted from a remote sensor or, turn on a flood light for a set amount of time when triggered by a remote PIR – all without any additional hardware. Serial port configuration also allows a modules zone and address (all SmartRFy modules default to zone and address 0) to be changed. This provides the option for modules to be placed into groups, which will then only respond to other modules with a matching zone or address.

Slave controlled

Example 1: Turning on a remote relay with zone = 1 and address = 5

Example 2: Send plain serial text “Hello” to a remote microcontroller

SmartRFy modules can also be controlled via their serial port by other devices such as microcontrollers or computer based automation software such as Node-RED. Using a SmartRFy module as a slave device (must be capable of transmitting/receiving) gives a master device the ability to monitor and control any other SmartRFy devices on the network, regardless of their zone and address. SmartRFy modules can even be used as a passive wireless serial port for passing non-SmartRFy data to other remotely connected devices.


Sensor module reference manual TBA

Libraries, example code, and diagrams are provided as an additional free service by Hobby Components and are not sold as part of this product. We do no provide any guarantees or warranties as to their accuracy or fitness for purpose.

Descriptions and diagrams on this page are copyright Hobby Components Ltd and may not be reproduced without permission.

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