RN4870 click

RN4870 click carries the RN4870 Bluetooth® 4.2 low energy module from Microchip. The click is designed to run on a 3.3V power supply. It uses ASCII Command Interface over UART for communication with target microcontroller, with additional functionality provided by the following pins on the mikroBUS™ line: PWM, INT, RST, CS.

RN4870 module features

The RN4080 module from Microchip provides a complete solution to implement Bluetooth 4.2 Low Energy connectivity.

All products in the RN series can be dynamically configured by the host microcontroller with a few simple ASCII commands.

The RN4870 supports both peripheral and central Generic Access Profile (GAP) roles, actively scanning for other connectable devices instead of waiting for incoming connection requests. The peripherals are usually small, low power devices like sensors and monitors, that broadcast information to the central device. The central device can communicate with multiple peripherals.

It also supports Remote Command mode which allows a remote device to access Command mode remotely via Bluetooth link. 

The module contains an integral ceramic chip antenna.

Specifications

Pinout diagram

This table shows how the pinout on RN4870 click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
	NC	1	AN	PWM	16	PWM	PWM1
Module Reset	RST	2	RST	INT	15	UART_CTS	UART Clear To Send
UART Ready To Send	UART_RTS	3	CS	TX	14	UART_TXD	UART Data output
	NC	4	SCK	RX	13	UART_RXD	UART Data input
	NC	5	MISO	SCL	12	GPIO1	GPIO
	NC	6	MOSI	SDA	11	GPIO2	GPIO
Power supply	+3.3V	7	3.3V	5V	10	NC
Ground	GND	8	GND	GND	9	GND	Ground

Additional pins

Buttons and LEDs

Maximum ratings

Programming

Code examples for RN4870 click, written for MikroElektronika hardware and compilers are available on Libstock.

Code snippet

The following code snippet shows send function for RN4xxx clicks. If the message type is correct, it will estabilish connection with the device specified by the address in the parameter and then send the properly formated data.

01 #define BTCMD( TXT ) UART2_Write_Text( TXT )
02 void RN4xxx_send(char *pAddr, T_RN4xxx_message msgData )
03 {
04    static char msgTxt [255];
05
06    if (msgData.msgType ==  'Q')
07    {
08        /*Connects to a device with specified adress*/
09        BTCMD("C,1,");
10        BTCMD (pAddr);
11        BTCMD("r");
12        Delay_ms(3000);
13        /*Secures the connection, entering data stream mode*/
14        BTCMD("Br");
15        Delay_ms(3000);
16    }
17    /*Sentence construction */
18    msgTxt[0] = '#';
19    msgTxt[1] = msgData.msgType;
20    msgTxt[2] = ',';
21    msgTxt[3] = msgData.dataType/0x100;
22    msgTxt[4] = msgData.dataType%0x100;
23    msgTxt[5] = ',';
24    msgTxt[6] = msgData.id;
25    msgTxt[7] = ',';
26    msgTxt[8] = '';
27    strcat (msgTxt, msgData.payload);
28    strcat (msgTxt, "*rn");
29
30    BTCMD ( msgTxt );
31
32    if (msgData.msgType ==  'Q')
33    {
34        Delay_ms(3000);
35        /*Enters CMD mode*/
36         BTCMD("$");
37        Delay_ms(100);
38        BTCMD("$$$");
39        Delay_ms(1000);
40        /*Kills connection*/
41        BTCMD("K,1r");
42        Delay_ms(500);
43    }
44 }