LR 4 Click Board™

How Does The LR 4 Click Board™Work?

The LR 4 Click Board™ as its foundation uses the 32001353, a low-power long-range RF technology-based transceiver module from Mipot. It offers a long-range spread spectrum communication with high interference immunity. The network is implemented as a star topology, where endpoints work in duty cycle mode, significantly reducing the overall power consumption. The LR 4 Click Board™ features an embedded LoRaWAN Class A and Class C compliant stack offering 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.

To join a LoRaWAN network, the 32001353 requires a LoRaWAN concentrator/gateway. The endpoint device has to use a unique endpoint address, an application session key, and a network session key. The first method is called over-the-air activation (OTAA), where these keys are issued after a specific join procedure. The second method is to assign these keys manually, using UART commands. This method is called activation by personalization (ABP) and can be prone to some security issues. In any case, before an end-device can communicate on the LoRaWAN network, it must be activated.

The LR 4 Click Board™ communicates with MCU using the UART interface with commonly used UART RX and TX pins at data rates up to 115200bps for the data transfer. In addition to these features, the 32001353 also uses several GPIO pins connected to the mikroBUS™ socket. The WK pin routed on the CS pin of the mikroBUS™ represents the Wake-up function used for waking up the device, while the RST pin on the mikroBUS™ socket can perform Hardware Reset function by putting this pin in a logic low state. This Click board™ also has an indicator routed on the INT pin of the mikroBUS ™ socket, which will provide the user with feedback after a successfully received package and verified checksum.

The LR 4 Click Board™ features the SMA antenna connector with an impedance of 50Ω, so it can be equipped with the appropriate 868MHz compliant antenna that MikroE has in its offer.

The LR 4 Click Board™can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. A proper logic voltage level conversion is performed by the TXB0106 voltage level shifter, while the LDO ensures that recommended values power the module. This allows for both 3.3V and 5V capable MCUs to use the UART communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

SPECIFICATIONS

PINOUT DIAGRAM

This table shows how the pinout of the LR 4 Click Board™ corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

ONBOARD SETTINGS AND INDICATORS

LR 4 CLICK ELECTRICAL SPECIFICATIONS