LoRa 3 Click Board
The LoRa 3 Click Board™ is a LoRa technology-based SRD transceiver, which operates at a sub-gigahertz frequency of 868MHz. Thanks to the spread spectrum modulation feature, as well as the low power consumption, it is capable of achieving a long-range communication, immune to interference. This Click Board™ features a complete LoRa stack on-board: it implements physical, network and MAC layers, allowing for easy operation via the UART interface. The transceiver is RED 2014/53/EU certified and compliant to REACH and RoHS regulations, allowing for an easy integration into the final application, reducing development time, costs, and time to market.
Lora RF technology based 868MHz transceiver
LoRa 3 Click is a LoRa technology based SRD transceiver, which operates at a sub-gigahertz frequency of 868MHz. Thanks to the spread spectrum modulation feature, as well as the low power consumption, it is capable of achieving a long-range communication, immune to interferences. This Click Board™' features a complete LoRa stack on-board: it implements physical, network and MAC layers, allowing for easy operation via the UART interface. The transceiver is RED 2014/53/EU certified and compliant to REACH and RoHS regulations, allowing for an easy integration into the final application, reducing development time, costs, and time to market.
Coupled with the AES128 message encryption, very small form factor, and low current consumption, LoRa 3 Click offers an easy and reliable solution for developing low power, highly integrated IoT networks, security systems, alarm networks, and similar applications that require simple and reliable networking solutions.
How Does it Work?
The heart of the LoRa 3 Click is a wireless transceiver module from Mipot company, labelled as 32001345. It is the LoRa RF technology-based long range transceiver, optimised for a robust wireless networking, immune to interference. The network is implemented as a star topology, where endpoints work in duty cycle mode, significantly reducing the overall power consumption. This allows endpoint nodes to be battery operated.
The communication is done via the UART interface. A communication between the module and the host MCU starts with the MCU pulling the NWAKE pin to a LOW logic state. This will wake up the module, after which the module expects the 0xAA code. This code is a header of every data packet that has been sent or received. After the header, a command code is sent, followed by the payload and the checksum. After a complete packet has been received and its checksum is verified, the module pulls the NDATA_INDICATE (ND_IND) to a LOW logic level. After a short timeout, the data (message) is sent via the UART TX pin of the module, back to the host MCU. At the end of the communication cycle, the ND_IND pin is pulled to a HIGH logic level and the module goes into the sleep mode, waiting to be awakened again by the NWAKE pin. Every command from the host results with a response from the module in the same format, with the command code ORed with 0x80. LoRa 3 Click can be configured to work as either END NODE or MASTER NODE, by using simple AT commands. While working as the MASTER NODE, the Click Board™' can use a set of master-specific commands, such as the pairing command. This command will add the end node which requested pairing, to the master network table. While working as the END NODE, LoRa 3 Click can issue slave specific commands/requests, such as the pairing request command, which will allow that end node to be paired with the master. However, the provided LoRa 3 Click library offers easy to use functions, which simplify configuration and communication tasks. Their usage is demonstrated in the included example application.
To allow interfacing with both 3.3V and 5V MCUs, this Click Board™' employs the TXB0106, a bidirectional level shifter and voltage translator from Texas Instruments. This translates the external voltage levels to acceptable levels that can be used on the Mipot LoRa module. All the I/O pins of the 32001345 LoRa module are routed via this IC to the mikroBUS pins.
The NWAKE pin from the 32001345 LoRa module is routed to the mikroBUS CS pin, while the UART RX and TX pins are routed to the appropriate mikroBUS UART pins, via the level shifter. ND_IND pin is routed to the INT pin of the mikroBUS - also via the level shifter - so it can be used to easily trigger an interrupt, or some other type of alert indicating that the module transmits data. The NRST pin is routed to the mikroBUS RST pin and it is used to reset the device. It is internally pulled up with a resistor.
The LoRa 3 Click Board™ features an SMA connector so it can be equipped with the appropriate 868MHz antenna. The on-board SMD jumper labelled as is used to select a voltage input for the level shifter for interfacing with 3.3V or 5V MCUs.
- LoRa 3 Click Board (1)