Radar Click

How does it work?

Radar Click as its foundation uses the MM5D91-00, a presence detection sensor module with an integrated mmWave technology from Jorjin Technologies Inc. It counts the number of people entering or exiting an entrance, simplifies the implementation of mmWave sensors in the band of 61.0 to 61.5GHz, and includes the ARM Cortex-M4F-based processor system 1Tx 3Rx antenna and onboard regulator. This Click board™ is built to demonstrate the function of the entrance counter of the 60GHz radar sensor with its sophisticated radar presence detection algorithms.

Characterized by low power consumption and high resolution, this board represents a suitable solution for various presence sensing applications, from office and home to commercial buildings and more. Its detection range goes up to 10m for macro motion, representing human movements, and 5m for micro motion, which stands for stationary human (normal breathing and blinking eyes) in sitting or standing positions with no active signs for at least 30 seconds. Immune to environmental factors such as temperature, wind, sunlight, and dust/debris, the MM5D91-00 also comes with azimuth and elevation field of view of ±45° and ±40°.

The MM5D91-00 communicates with MCU using the UART interface with the default baud rate of 115200bps for the data transfer. In addition, it also uses several mikroBUS™ pins. An active-low reset signal routed on the RST pin of the mikroBUS™ socket activates a hardware reset of the radar module. It also has three general-purpose pins, routed to the AN, PWM, and INT pins of the mikroBUS™ socket marked as GP2, GP1, and GP0 to signal an essential change in device status, alongside its green, red, and blue LED indicators. Green LED stands for active presence indication, while red LED represents non-presence indication. Blue LED serves for bootloader mode indication.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. However, the Click board™ comes equipped with a library that contains 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 on Radar Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
General Purpose 2	GP2	1	AN	PWM	16	GP1	General Purpose 1
Reset	RST	2	RST	INT	15	GP0	General Purpose 0
	NC	3	CS	RX	14	TX	UART TX
	NC	4	SCK	TX	13	RX	UART RX
	NC	5	MISO	SCL	12	NC
	NC	6	MOSI	SDA	11	NC
Power Supply	3.3V	7	3.3V	5V	10	5V	Power Supply
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

Radar Click electrical specifications

Software Support

We provide a library for the Radar Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for Radar Click driver.

Key functions

• radar_get_event This function waits for an IN/OUT event or ACK command response.

• radar_get_temperature This function reads the chip internal temperature.

• radar_set_detection_range This function sets the min and max presence detection values.

Example Description

This example demonstrates the use of Radar Click board™ by reading and parsing events as well as the module internal temperature.

void application_task ( void ) 
 { 
     uint8_t evt_id, evt_payload_size, evt_payload[ 16 ]; 
     if ( RADAR_OK == radar_get_event ( &radar, &evt_id, evt_payload, &evt_payload_size ) ) 
     { 
         if ( RADAR_CMD_ID_DETECT_IN_EVT == evt_id ) 
         { 
             log_printf( &logger, " EVENT: INrn" ); 
             radar_float_bytes_t distance; 
             memcpy ( distance.b_data, &evt_payload[ 8 ], 4 ); 
             radar_float_ieee_to_mchip ( &distance.f_data ); 
             log_printf( &logger, " Target distance: %.3f mrn", distance.f_data ); 
             memcpy ( distance.b_data, &evt_payload[ 12 ], 4 ); 
             radar_float_ieee_to_mchip ( &distance.f_data ); 
             log_printf( &logger, " Accuracy (+/-): %.3f mrn", distance.f_data ); 
         } 
         else 
         { 
             log_printf( &logger, " EVENT: OUTrn" ); 
         } 
         uint32_t evt_time = ( ( uint32_t ) evt_payload[ 3 ] << 24 ) | ( ( uint32_t ) evt_payload[ 2 ] << 16 ) |  
                             ( ( uint16_t ) evt_payload[ 1 ] << 8 ) | evt_payload[ 0 ]; 
         log_printf( &logger, " Elapsed time: %.2f srn", evt_time / 1000.0 ); 
         float temperature; 
         if ( RADAR_OK == radar_get_temperature ( &radar, &temperature ) ) 
         { 
             log_printf( &logger, " Temperature: %.2f Crnn", temperature ); 
         } 
     } 
 }

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager(recommended way), downloaded from our LibStock™ or found on Mikroe github account.

Other Mikroe Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.Radar

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MikroElektronika compilers.

mikroSDK

This Click board™ is supported with mikroSDK – MikroElektronika Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from the LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.