1 // Unknown 433Mhz weather sensor decoder. Untested in the real world.
2 // http://arduino.cc/forum/index.php/topic,142871.msg1106336.html#msg1106336
6 // |_________| |______| |___| |
9 // | 9780us | 4420us | 2410us
13 #define DataBits0 4 // Number of data0 bits to expect
14 #define DataBits1 32 // Number of data1 bits to expect
15 #define allDataBits 36 // Number of data sum 0+1 bits to expect
16 // isrFlags bit numbers
17 #define F_HAVE_DATA 1 // 0=Nothing in read buffer, 1=Data in read buffer
18 #define F_GOOD_DATA 2 // 0=Unverified data, 1=Verified (2 consecutive matching reads)
19 #define F_CARRY_BIT 3 // Bit used to carry over bit shift from one long to the other
20 #define F_STATE 7 // 0=Sync mode, 1=Data mode
25 const unsigned long sync_MIN = 9600; // Minimum Sync time in micro seconds
26 const unsigned long sync_MAX = 9900;
28 const unsigned long bit1_MIN = 4200;
29 const unsigned long bit1_MAX = 4600;
31 const unsigned long bit0_MIN = 2200;
32 const unsigned long bit0_MAX = 2600;
34 const unsigned long glitch_Length = 300; // Anything below this value is a glitch and will be ignored.
36 // Interrupt variables
37 unsigned long fall_Time = 0; // Placeholder for microsecond time when last falling edge occured.
38 unsigned long rise_Time = 0; // Placeholder for microsecond time when last rising edge occured.
39 byte bit_Count = 0; // Bit counter for received bits.
40 unsigned long build_Buffer[] = {0,0}; // Placeholder last data packet being received.
41 volatile unsigned long read_Buffer[] = {0,0}; // Placeholder last full data packet read.
42 volatile byte isrFlags = 0; // Various flag bits
44 void PinChangeISR0(){ // Pin 2 (Interrupt 0) service routine
45 unsigned long Time = micros(); // Get current time
46 if (digitalRead(2) == LOW) {
48 if (Time > (rise_Time + glitch_Length)) {
50 Time = micros() - fall_Time; // Subtract last falling edge to get pulse time.
51 if (bitRead(build_Buffer[1],31) == 1)
52 bitSet(isrFlags, F_CARRY_BIT);
54 bitClear(isrFlags, F_CARRY_BIT);
56 if (bitRead(isrFlags, F_STATE) == 1) {
58 if ((Time > bit0_MIN) && (Time < bit0_MAX)) {
60 build_Buffer[1] = build_Buffer[1] << 1;
61 build_Buffer[0] = build_Buffer[0] << 1;
62 if (bitRead(isrFlags,F_CARRY_BIT) == 1)
63 bitSet(build_Buffer[0],0);
66 else if ((Time > bit1_MIN) && (Time < bit1_MAX)) {
68 build_Buffer[1] = build_Buffer[1] << 1;
69 bitSet(build_Buffer[1],0);
70 build_Buffer[0] = build_Buffer[0] << 1;
71 if (bitRead(isrFlags,F_CARRY_BIT) == 1)
72 bitSet(build_Buffer[0],0);
76 // Not a 0 or 1 bit so restart data build and check if it's a sync?
80 bitClear(isrFlags, F_GOOD_DATA); // Signal data reads dont' match
81 bitClear(isrFlags, F_STATE); // Set looking for Sync mode
82 if ((Time > sync_MIN) && (Time < sync_MAX)) {
84 bitSet(isrFlags, F_STATE); // Set data mode
87 if (bit_Count >= allDataBits) {
89 bitClear(isrFlags, F_GOOD_DATA); // Assume data reads don't match
90 if (build_Buffer[0] == read_Buffer[0]) {
91 if (build_Buffer[1] == read_Buffer[1])
92 bitSet(isrFlags, F_GOOD_DATA); // Set data reads match
94 read_Buffer[0] = build_Buffer[0];
95 read_Buffer[1] = build_Buffer[1];
96 bitSet(isrFlags, F_HAVE_DATA); // Set data available
97 bitClear(isrFlags, F_STATE); // Set looking for Sync mode
98 digitalWrite(13,HIGH); // Used for debugging
106 if ((Time > sync_MIN) && (Time < sync_MAX)) {
111 bitSet(isrFlags, F_STATE); // Set data mode
112 digitalWrite(13,LOW); // Used for debugging
115 fall_Time = micros(); // Store fall time
120 if (Time > (fall_Time + glitch_Length)) {
122 rise_Time = Time; // Store rise time
129 pinMode(13,OUTPUT); // Used for debugging
132 Serial.println(F("ISR Pin 2 Configured For Input."));
133 attachInterrupt(0,PinChangeISR0,CHANGE);
134 Serial.println(F("Pin 2 ISR Function Attached. Here we go."));
138 if (bitRead(isrFlags,F_GOOD_DATA) == 1) {
144 void serial_dump(void) {
145 unsigned long myData0 = 0;
146 unsigned long myData1 = 0;
148 // We have at least 2 consecutive matching reads
149 myData0 = read_Buffer[0]; // first 4 bits
150 myData1 = read_Buffer[1]; // rest of 32 bits
151 bitClear(isrFlags,F_HAVE_DATA); // Flag we have read the data
154 Serial.print("# 0=");
155 dec2binLong(myData0,DataBits0);
157 dec2binLong(myData1,DataBits1);
161 Serial.print("temp=");
162 int temp = ( myData1 >> 8 ) & 0xFFF;
163 if ( temp & 0x800 ) temp = temp | 0xF000;
164 Serial.print(temp / 10.0, 1);
166 Serial.print(" humidity=");
167 Serial.print( myData1 & 0xFF );
169 byte b1 = ( myData1 >> 20 ); // second byte from received packet
171 Serial.print(" button=");
172 Serial.print( b1 & 0x04);
174 Serial.print(" battery=");
175 Serial.print( b1 & 0x08);
177 Serial.print(" channel=");
178 Serial.print( ( b1 & 0x03 ) + 1 );
180 Serial.print(" rid=");
181 Serial.println( myData1 >> 24 );
183 // remote but so we don't see this packet again
184 bitClear(isrFlags, F_GOOD_DATA);
188 void dec2binLong(unsigned long myNum, byte NumberOfBits) {
189 if (NumberOfBits <= 32){
190 myNum = myNum << (32 - NumberOfBits);
191 for (int i=0; i<NumberOfBits; i++) {
192 if (bitRead(myNum,31) == 1)
197 if ( i % 4 == 3 ) Serial.print(" ");