wayne roberts / Mbed OS alarm_slave

raises pin at time instructed by received LoRa packet.

Dependencies:   sx126x sx12xx_hal

radio chip selection

Radio chip driver is not included, allowing choice of radio device.
If you're using SX1272 or SX1276, then import sx127x driver into your program.
if you're using SX1261 or SX1262, then import sx126x driver into your program.
if you're using SX1280, then import sx1280 driver into your program.
If you're using NAmote72 or Murata discovery, then you must import only sx127x driver.

Transmitter side is at Alarm Slave project page.
Output is observed on nucleo morpho connector pins pin[A-D]: see code for actual pins used.

main.cpp

Committer:
dudmuck
Date:
2018-01-26
Revision:
2:bf201940a9db
Parent:
1:6a3a48d657a9
Child:
3:f81d64ff0164

File content as of revision 2:bf201940a9db:

#include "sx127x_lora.h"
 
DigitalOut myled(LED1);
#ifdef TARGET_DISCO_L072CZ_LRWAN1

    SPI spi(PA_7, PA_6, PB_3); // mosi, miso, sclk
    //           dio0, dio1,  nss,  spi,  rst
    SX127x radio(PB_4, PB_1, PA_15, spi, PC_0);
    
    #define CRF1    PA_1
    #define CRF2    PC_2
    #define CRF3    PC_1
    DigitalOut Vctl1(CRF1);
    DigitalOut Vctl2(CRF2);
    DigitalOut Vctl3(CRF3);    
    
    void rfsw_callback()
    {
        if (radio.RegOpMode.bits.Mode == RF_OPMODE_TRANSMITTER) {
            Vctl1 = 0;        
            if (radio.RegPaConfig.bits.PaSelect) {
                Vctl2 = 0;
                Vctl3 = 1;                        
            } else {
                Vctl2 = 1;
                Vctl3 = 0;            
            }
        } else {
            if (radio.RegOpMode.bits.Mode == RF_OPMODE_RECEIVER || radio.RegOpMode.bits.Mode == RF_OPMODE_RECEIVER_SINGLE)
                Vctl1 = 1;
            else
                Vctl1 = 0;
            
            Vctl2 = 0;
            Vctl3 = 0;        
        }
    }    
    
    DigitalOut pinA(PB_12);
    DigitalOut pinB(PB_13);
    DigitalOut pinC(PB_14);
    DigitalOut pinD(PB_15);
#else
    SPI spi(D11, D12, D13); // mosi, miso, sclk
    //           dio0, dio1, nss, spi, rst
    SX127x radio(  D2,   D3, D10, spi, A0); // sx1276 arduino shield
    
    DigitalInOut rfsw(A4);    // for SX1276 arduino shield
     
    void rfsw_callback()
    {
        if (radio.RegOpMode.bits.Mode == RF_OPMODE_TRANSMITTER)
            rfsw = 1;
        else
            rfsw = 0;
    }
    
    DigitalOut pinA(PC_3);
    DigitalOut pinB(PC_2);
    DigitalOut pinC(PC_6);
    DigitalOut pinD(PC_8);
#endif /* !TARGET_DISCO_L072CZ_LRWAN1 */

/**********************************************************************/
SX127x_lora lora(radio);

DigitalOut* pin; 
Timeout to;

#define PIN_ASSERT_us       500000

#define CMD_PINA       0x02
#define CMD_PINB       0x03
#define CMD_PINC       0x06
#define CMD_PIND       0x08

void alarm_pin_clr()
{
    pin->write(0);
}

void alarm_pin_set()
{
    pin->write(1);
    to.attach_us(&alarm_pin_clr, PIN_ASSERT_us);
}

static uint16_t crc_ccitt( uint8_t *buffer, uint16_t length )
{
    // The CRC calculation follows CCITT
    const uint16_t polynom = 0x1021;
    // CRC initial value
    uint16_t crc = 0x0000;

    if( buffer == NULL )
    {
        return 0;
    }

    for( uint16_t i = 0; i < length; ++i )
    {
        crc ^= ( uint16_t ) buffer[i] << 8;
        for( uint16_t j = 0; j < 8; ++j )
        {
            crc = ( crc & 0x8000 ) ? ( crc << 1 ) ^ polynom : ( crc << 1 );
        }
    }

    return crc;
}

void get_alarm()
{
    uint16_t rx_crc, crc = crc_ccitt(radio.rx_buf, 5);
    rx_crc = radio.rx_buf[5];
    rx_crc <<= 8;
    rx_crc += radio.rx_buf[6];
    //printf("%u) crc rx:%04x, calc:%04x\r\n", lora.RegRxNbBytes, rx_crc, crc);
    if (crc == rx_crc) {
        uint8_t c = radio.rx_buf[0];
        //if (radio.rx_buf[0] == CMD_ALARM)
        if (c == CMD_PINA || c == CMD_PINB || c == CMD_PINC || c == CMD_PIND) {
            unsigned delay;
            delay = radio.rx_buf[1];
            delay <<= 8;
            delay += radio.rx_buf[2];
            delay <<= 8;
            delay += radio.rx_buf[3];
            delay <<= 8;
            delay += radio.rx_buf[4];
            switch (c) {
                case CMD_PINA: pin = &pinA; break;
                case CMD_PINB: pin = &pinB; break;
                case CMD_PINC: pin = &pinC; break;
                case CMD_PIND: pin = &pinD; break;
            }
            to.attach_us(&alarm_pin_set, delay);
            printf("delay:%u\r\n", delay);
        } else
            printf("cmd? %02x\r\n", radio.rx_buf[0]);
    } else
        printf("crc fail %04x, %04x\r\n", rx_crc, crc);
}
 
int main()
{   
    printf("\r\nreset-rx\r\n");
    radio.rf_switch = rfsw_callback;
    
    radio.set_frf_MHz(910.8);
    lora.enable();
    lora.setBw_KHz(500);
    lora.setSf(11);
    
    radio.RegPaConfig.octet = radio.read_reg(REG_PACONFIG);    
#ifdef TARGET_DISCO_L072CZ_LRWAN1
    radio.RegPaConfig.bits.PaSelect = 1;
#else
    /* RFO or PABOOST choice:
     * SX1276 shield: RFO if using 900MHz, or PA_BOOST if using 433MHz
     */
    rfsw.input();
    if (rfsw.read()) {
        printf("LAS\r\n");
        /* LAS HF=PA_BOOST  LF=RFO */
        if (radio.HF)
            radio.RegPaConfig.bits.PaSelect = 1;
        else
            radio.RegPaConfig.bits.PaSelect = 0;
    } else {
        /* MAS shield board, only RFO TX */
        radio.RegPaConfig.bits.PaSelect = 0;
        printf("MAS\r\n");
    }
    rfsw.output();
#endif /* !TARGET_DISCO_L072CZ_LRWAN1 */
    radio.write_reg(REG_PACONFIG, radio.RegPaConfig.octet);
                
    lora.start_rx(RF_OPMODE_RECEIVER);
    
    for (;;) {     
        if (lora.service() == SERVICE_READ_FIFO) {
            /*int i;
            for (i = 0; i < lora.RegRxNbBytes; i++) {
                printf("%02x ", radio.rx_buf[i]);
            }
            printf("\r\n");*/
            get_alarm();
        }
    }
}