+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include <inttypes.h>
+
+#define RF433_PIN 10
+//********************************************************************//
+
+typedef unsigned char byte;
+
+typedef struct {
+ byte offset;
+ byte state;
+} rf_bit_t;
+
+// offset is number of alphas (0.08ms)
+
+const rf_bit_t zero_bit[] = { { 4, 1 },
+ { 16, 0 },
+ { 20, 1 },
+ { 32, 0 },
+ { 0, 0 } };
+
+const rf_bit_t one_bit[] = { { 12, 1 },
+ { 16, 0 },
+ { 28, 1 },
+ { 32, 0 },
+ { 0, 0 } };
+
+const rf_bit_t float_bit[] = { { 4, 1 },
+ { 16, 0 },
+ { 28, 1 },
+ { 32, 0 },
+ { 0, 0 } };
+
+const rf_bit_t sync_bit[] = { { 4, 1 },
+ { 128, 0 },
+ { 0, 0 } };
+
+typedef enum { ZERO = 0, ONE , FLOAT , SYNC } adbit_t;
+typedef byte ad_bit_t;
+#define WORD_LEN 13
+typedef ad_bit_t word_t[WORD_LEN];
+
+const rf_bit_t* bit_defs[] = { zero_bit, one_bit, float_bit, sync_bit };
+
+byte alpha_cnt = 0;
+byte bit_cnt = 0;
+byte chunk_cnt = 0;
+byte word_cnt = 0;
+const ad_bit_t* current_word;
+byte volatile frame_finished = 1;
+
+#define FRAME_LEN 8
+
+#define A1_ON 0
+#define A1_OFF 1
+#define A2_ON 2
+#define A2_OFF 3
+
+#define B1_ON 4
+#define B1_OFF 5
+#define B2_ON 6
+#define B2_OFF 7
+
+#define C1_ON 8
+#define C1_OFF 9
+#define C2_ON 10
+#define C2_OFF 11
+
+#define D1_ON 12
+#define D1_OFF 13
+#define D2_ON 14
+#define D2_OFF 15
+
+const word_t words[] = {
+{ ZERO, ZERO, FLOAT, FLOAT, ZERO, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, FLOAT, SYNC }, // A1_ON
+{ ZERO, ZERO, FLOAT, FLOAT, ZERO, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, SYNC }, // A1_OFF
+{ ZERO, ZERO, FLOAT, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, FLOAT, SYNC }, // A2_ON
+{ ZERO, ZERO, FLOAT, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, SYNC }, // A2_OFF
+
+{ FLOAT, ZERO, FLOAT, FLOAT, ZERO, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, FLOAT, SYNC }, // B1_ON
+{ FLOAT, ZERO, FLOAT, FLOAT, ZERO, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, SYNC }, // B1_OFF
+{ FLOAT, ZERO, FLOAT, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, FLOAT, SYNC }, // B2_ON
+{ FLOAT, ZERO, FLOAT, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, SYNC }, // B2_OFF
+
+{ ZERO, FLOAT, FLOAT, FLOAT, ZERO, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, FLOAT, SYNC }, // C1_ON
+{ ZERO, FLOAT, FLOAT, FLOAT, ZERO, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, SYNC }, // C1_OFF
+{ ZERO, FLOAT, FLOAT, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, FLOAT, SYNC }, // C2_ON
+{ ZERO, FLOAT, FLOAT, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, SYNC }, // C2_OFF
+
+{ FLOAT, FLOAT, FLOAT, FLOAT, ZERO, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, FLOAT, SYNC }, // D1_ON
+{ FLOAT, FLOAT, FLOAT, FLOAT, ZERO, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, SYNC }, // D1_OFF
+{ FLOAT, FLOAT, FLOAT, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, FLOAT, SYNC }, // D2_ON
+{ FLOAT, FLOAT, FLOAT, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, FLOAT, FLOAT, ZERO, SYNC } // D2_OFF
+};
+
+
+//********************************************************************//
+
+void start_timer()
+{
+ // timer 1: 2 ms
+ TCCR1A = 0; // prescaler 1:8, WGM = 4 (CTC)
+ TCCR1B = 1<<WGM12 | 1<<CS11; //
+ OCR1A = 159; // (1+159)*8 = 1280 -> 0.08ms @ 16 MHz -> 1*alpha
+// OCR1A = 207; // (1+207)*8 = 1664 -> 0.104ms @ 16 MHz -> 1*alpha
+ TCNT1 = 0; // reseting timer
+ TIMSK1 = 1<<OCIE1A; // enable Interrupt
+}
+
+void stop_timer() // stop the timer
+{
+ // timer1
+ TCCR1B = 0; // no clock source
+ TIMSK1 = 0; // disable timer interrupt
+}
+
+union {
+ byte uint8[4];
+ uint32_t uint32;
+} rf433_data;
+byte rf433_hi_cnt=0;
+byte rf433_lo_cnt=0;
+byte last_sample=0;
+int valid=0;
+ISR(TIMER1_COMPA_vect)
+{
+ byte sample = digitalRead(RF433_PIN);
+ if (last_sample!=sample && sample==HIGH)
+ {
+ if ( rf433_lo_cnt > 2 && rf433_lo_cnt<6 && rf433_hi_cnt>10 && rf433_hi_cnt < 14)
+ {
+ rf433_data.uint32<<=1;
+ rf433_data.uint32|=1;
+ valid++;
+ } else if (rf433_hi_cnt > 2 && rf433_hi_cnt<6 && rf433_lo_cnt>10 && rf433_lo_cnt < 14) {
+ rf433_data.uint32<<=1;
+ valid++;
+ } else if (rf433_hi_cnt > 2 && rf433_hi_cnt<6 && rf433_lo_cnt>120 && rf433_lo_cnt < 128 && valid >=24) {
+ //rf433_data.uint8[3]=0;
+ //Serial.print(rf433_data.uint32);
+ Serial.print(rf433_data.uint8[0],BYTE);
+ Serial.print(rf433_data.uint8[1],BYTE);
+ Serial.print(rf433_data.uint8[2],BYTE);
+ //Serial.print(rf433_data.uint8[3],BYTE);
+ } else {
+ valid=0;
+ rf433_data.uint32=0;
+ }
+ rf433_hi_cnt=0;
+ rf433_lo_cnt=0;
+ }
+ if (sample == HIGH)
+ rf433_hi_cnt++;
+ else
+ rf433_lo_cnt++;
+ last_sample=sample;
+}
+
+//unsigned long wm_start_[3]={0,0,0};
+//bool wait_millis(unsigned long *start_time, unsigned long ms)
+//{
+// if (ms == 0)
+// return false;
+// else if (*start_time > 0)
+// {
+// if (millis() < *start_time || millis() > (*start_time) + ms)
+// {
+// *start_time = 0;
+// return false;
+// }
+// else
+// return true;
+// }
+// else
+// {
+// *start_time=millis();
+// return true;
+// }
+//}
+
+//********************************************************************//
+
+void setup()
+{
+ pinMode(RF433_PIN, INPUT); // set pin to input
+ digitalWrite(RF433_PIN, LOW); // turn of pullup resistors
+
+ Serial.begin(57600);
+// Serial.println("starting timer");
+ start_timer();
+}
+
+
+void loop()
+{
+}