BLE2 click

BLE2 click is an excellent choice if you want simple, temporary connectivity with your smart devices over Bluetooth 4.1.

BLE2 click features the RN4020 module from Microchip, that integrates RF, a baseband controller, and a command API processor, making it a complete Bluetooth Low Energy solution. The click communicates with the target board MCU through mikroBUS™ RX, TX and AN (CMD), PWM (con.), and RST (wake) lines. The board is designed to use 3.3V power supply only.

Microchip Low-energy Data Profile

The RN4020 has Microchip’s Low-energy Data Profile (MLDP) which enables an asynchronous serial data connection between two RN4020 devices (which could be two BLE2 clicks). The module can be remotely controlled or updated over-the-air by another module over a secure connection or can be controlled or updated through its UART interface.

PCB trace antenna

The RN4020 module aboard BLE2 click incorporates a PCB antenna with a range of at least 30m. 

Bluetooth 4.1

Bluetooth 4.1 is intended for IoT, it has low power consumption and lets any device be a peripheral and a hub at the same time.

Specifications

Pinout diagram

This table shows how the pinout on BLE2 click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
Indicates connection state	CONN	1	AN	PWM	16	CMD/MLDP	Command or MLDP mode
Deep Sleep Wake	SWAKE	2	RST	INT	15	NC
	NC	3	CS	TX	14	BT_UART_TX	UART Transmit
	NC	4	SCK	RX	13	BT_UART_RX	UART Receive
	NC	5	MISO	SCL	12	NC
	NC	6	MOSI	SDA	11	NC
Power supply	+3.3V	7	3.3V	5V	10	NC
Ground	GND	8	GND	GND	9	GND	Ground

Programming

The code sets up the BLE2 click board, and sends messages through Bluetooth low energy every 5 seconds. If the BLE2 click board receives messages over Bluetooth low energy, the code displays the message and updates the buffer.

01 void main() {
02   Display_Init();
03   MCU_Init();
04   #ifdef INIT_BLE
05   BLE_Init();
06   delay_ms(2000);
07   #else
08   RN_WAKE = 1;
09   wait_response("CMD");
10   #endif
11   DrawFrame();
12   InitTimer2();
13   while(1)
14   {
15     if(data_ready)
16     {
17       //If characteristic is configured as write
18       //received messages come here
19       Display_Message();
20       reset_buff();
21     }
22     else
23     {
24        //Test: every 5sec increase baterry level (0 to 100%)
25        //and send value via Bluetooth Low Energy
26        if (tmr_flg)
27        {
28           batt_level++;
29           if(batt_level > 100)
30           {
31             batt_level = 0;
32           }
33           Display_BatteryLevel();
34           if(RN_CONN)
35           { //send battery level value if BLE connected
36             shorttohex(batt_level, batt_level_txt);
37             ltrim(batt_level_txt);
38             ble2_write_server_characteristic_value_via_UUID("2A19",batt_level_txt);
39           }
40           tmr_flg = 0;
41        }
42     }
43   }
44 }