WiFi_433_Transceiver/main/Sensors/ClasOSensor.c

#include "ClasOSensor.h"
#include <stdint.h>
#include <stdio.h>
#include "../rxTimer.h"
#include "../led.h"

enum
{
    UNKNOWN,
    T0,
    T1,
    T2,
    T3,
    TEMP1_OK,
    DONE
};

static uint8_t rx_state = UNKNOWN;

static uint64_t sensor_data;
static uint32_t rx_numBits;

void ClasO_ResetDecoder()
{
    sensor_data = 0;
    rx_numBits = 0;
    rx_state = UNKNOWN;
}

static void addBit(uint8_t value)
{

    rx_numBits++;
    sensor_data = (sensor_data << 1) + (value & 0x01);

    rx_state = TEMP1_OK;
}

static int32_t rx_decode(uint32_t width)
{
    switch (rx_state) {
        case UNKNOWN: // Start of frame
            if (3700 <= width && width <= 4150)
            {
                rx_state = T0;
            }
            else
            {
                return -1; // error, reset
            }
            break;

        case T0: // First half of pulse : HIGH around 230us

            if (rx_numBits == 32)
            { // end of frame
                rx_state = DONE;
                //printf("c");
                sensor_data = (sensor_data >> 8); // Mask away some bits at the end
                return 1;
            }
            else if (420 <= width && width <= 560)
            {
                rx_state = T1;
            }
            else
            {
                if (rx_numBits == 0 && 3700 <= width && width <= 4150 )
                {
                    rx_state = T0;
                }
                else
                {
                    return -1; // error, reset
                }
            }
            break;

        case T1:
            if (880 <= width && width <= 1080)
            {
                addBit(0);
            }
            else if (1800 <= width && width <= 2100)
            {
                //debug_width = width;
                addBit(1);
            }
            else
            {
                return -1; // error, reset
            }
            rx_state = T0;
            break;
    }
    return 0;
}

int64_t nextPulseClasOSensor(uint32_t width)
{
    static int64_t previous_data = 0;
    static uint32_t old_time=0;
    static uint32_t now;
    int64_t retVal = -1;

    if (width > 0)
    {
        if (rx_state != DONE)
        {
            switch (rx_decode(width))
            {
            case -1:
                ClasO_ResetDecoder();
                break;
            case 1:
                rx_state = DONE;
                //printf("%d\n",debug_width);
                break;
            }
        }
    }
    if (rx_state == DONE) {
        now = millis();
        if( sensor_data != previous_data || (now > (old_time+1000)) ) {
            previous_data = sensor_data;
            retVal = sensor_data;
            blinkTheLED();
        }
        old_time = now;
        ClasO_ResetDecoder();
    }
    
    return retVal;
}