File content as of revision 5:1652e04809fb:

#include "platform.h"
 
SX127x_lora lora(radio);
Timer t;
#define CMD_PINA       0x02
#define CMD_PINB       0x03
#define CMD_PINC       0x06
#define CMD_PIND       0x08

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 transmit(unsigned target, uint8_t cmd)
{
    unsigned t_diff;
    uint16_t crc;

    radio.tx_buf[0] = cmd;
    t_diff = target - t.read_us();
    radio.tx_buf[1] = t_diff >> 24;
    radio.tx_buf[2] = t_diff >> 16;
    radio.tx_buf[3] = t_diff >> 8;
    radio.tx_buf[4] = t_diff & 0xff;
    crc = crc_ccitt(radio.tx_buf, 5);
    radio.tx_buf[5] = crc >> 8;
    radio.tx_buf[6] = crc & 0xff;


    lora.start_tx(lora.RegPayloadLength);   /* begin transmission */

    while (lora.service() != SERVICE_TX_DONE) {  /* wait for transmission to complete */
    }

    printf("t_diff:%u crc:%04x\r\n", t_diff, crc);
}

#define TARGET_LATENCY      2000000
void send_alarm(uint8_t cmd)
{
    int i;
    unsigned target = t.read_us() + TARGET_LATENCY;
    printf("send_alarm() %u\n", target);

    for (i = 0; i < 5; i++) {
        transmit(target, cmd);
        wait(0.1);
    }
}

void debounce(DigitalIn* pin, uint8_t cmd)
{
    if (!pin->read()) {
        int i;
        for (i = 0; i < 5; i++) {
            wait(0.01);
            if (pin->read()) {
                printf("trans\r\n");
                break;
            }
        }
        if (i == 5)
            send_alarm(cmd);

        while (!pin->read())
            ;
    }
}

void cmd_ocp(uint8_t ma)
{
    if (ma < 130)
        radio.RegOcp.bits.OcpTrim = (ma - 45) / 5;
    else
        radio.RegOcp.bits.OcpTrim = (ma + 30) / 10;
    radio.write_reg(REG_OCP, radio.RegOcp.octet);
   
    radio.RegOcp.octet = radio.read_reg(REG_OCP);
    if (radio.RegOcp.bits.OcpTrim < 16)
        ma = 45 + (5 * radio.RegOcp.bits.OcpTrim);
    else if (radio.RegOcp.bits.OcpTrim < 28)
        ma = (10 * radio.RegOcp.bits.OcpTrim) - 30;
    else
        ma = 240;
    printf("Ocp: %dmA\r\n", ma); 
}

int main()
{
    printf("\r\nreset-tx\r\n");
    t.start();

    pinA.mode(PullUp);
    pinB.mode(PullUp);
    pinC.mode(PullUp);
    pinD.mode(PullUp);

    radio.rf_switch = rfsw_callback;
    
    radio.set_frf_MHz(910.8);
    lora.enable();
    lora.setBw_KHz(500);
    lora.setSf(11);
    
    board_init();
                
    /* constant payload length */
    lora.RegPayloadLength = 7;
    radio.write_reg(REG_LR_PAYLOADLENGTH, lora.RegPayloadLength);
    
/*    lora.RegModemConfig2.octet = radio.read_reg(REG_LR_MODEMCONFIG2);
    lora.RegModemConfig2.sx1276bits.TxContinuousMode = 1;   
    radio.write_reg(REG_LR_MODEMCONFIG2, lora.RegModemConfig2.octet);      
*/
    for (;;) {       
        debounce(&pinA, CMD_PINA);
        debounce(&pinB, CMD_PINB);
        debounce(&pinC, CMD_PINC);
        debounce(&pinD, CMD_PIND);
    } // ..for (;;)
}