Diff: ir_RC5_RC6.cpp

Revision:

0:70c8e56bac45

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ir_RC5_RC6.cpp	Sat Jan 23 06:16:48 2016 +0000
@@ -0,0 +1,207 @@
+#include "IRremote.h"
+#include "IRremoteInt.h"
+
+//+=============================================================================
+// Gets one undecoded level at a time from the raw buffer.
+// The RC5/6 decoding is easier if the data is broken into time intervals.
+// E.g. if the buffer has MARK for 2 time intervals and SPACE for 1,
+// successive calls to getRClevel will return MARK, MARK, SPACE.
+// offset and used are updated to keep track of the current position.
+// t1 is the time interval for a single bit in microseconds.
+// Returns -1 for error (measured time interval is not a multiple of t1).
+//
+#if (DECODE_RC5 || DECODE_RC6)
+int  IRrecv::getRClevel (decode_results *results,  int *offset,  int *used,  int t1)
+{
+	int  width;
+	int  val;
+	int  correction;
+	int  avail;
+
+	if (*offset >= results->rawlen)  return SPACE ;  // After end of recorded buffer, assume SPACE.
+	width      = results->rawbuf[*offset];
+	val        = ((*offset) % 2) ? MARK : SPACE;
+	correction = (val == MARK) ? MARK_EXCESS : - MARK_EXCESS;
+
+	if      (MATCH(width, (  t1) + correction))  avail = 1 ;
+	else if (MATCH(width, (2*t1) + correction))  avail = 2 ;
+	else if (MATCH(width, (3*t1) + correction))  avail = 3 ;
+	else                                         return -1 ;
+
+	(*used)++;
+	if (*used >= avail) {
+		*used = 0;
+		(*offset)++;
+	}
+
+	DBG_PRINTLN( (val == MARK) ? "MARK" : "SPACE" );
+
+	return val;
+}
+#endif
+
+//==============================================================================
+// RRRR    CCCC  55555
+// R   R  C      5
+// RRRR   C      5555
+// R  R   C          5
+// R   R   CCCC  5555
+//
+// NB: First bit must be a one (start bit)
+//
+#define MIN_RC5_SAMPLES     11
+#define RC5_T1             889
+#define RC5_RPT_LENGTH   46000
+
+//+=============================================================================
+#if SEND_RC5
+void  IRsend::sendRC5 (unsigned long data,  int nbits)
+{
+	// Set IR carrier frequency
+	enableIROut(36);
+
+	// Start
+	mark(RC5_T1);
+	space(RC5_T1);
+	mark(RC5_T1);
+
+	// Data
+	for (unsigned long  mask = 1UL << (nbits - 1);  mask;  mask >>= 1) {
+		if (data & mask) {
+			space(RC5_T1); // 1 is space, then mark
+			mark(RC5_T1);
+		} else {
+			mark(RC5_T1);
+			space(RC5_T1);
+		}
+	}
+
+	space(0);  // Always end with the LED off
+}
+#endif
+
+//+=============================================================================
+#if DECODE_RC5
+bool  IRrecv::decodeRC5 (decode_results *results)
+{
+	int   nbits;
+	long  data   = 0;
+	int   used   = 0;
+	int   offset = 1;  // Skip gap space
+
+	if (irparams.rawlen < MIN_RC5_SAMPLES + 2)  return false ;
+
+	// Get start bits
+	if (getRClevel(results, &offset, &used, RC5_T1) != MARK)   return false ;
+	if (getRClevel(results, &offset, &used, RC5_T1) != SPACE)  return false ;
+	if (getRClevel(results, &offset, &used, RC5_T1) != MARK)   return false ;
+
+	for (nbits = 0;  offset < irparams.rawlen;  nbits++) {
+		int  levelA = getRClevel(results, &offset, &used, RC5_T1);
+		int  levelB = getRClevel(results, &offset, &used, RC5_T1);
+
+		if      ((levelA == SPACE) && (levelB == MARK ))  data = (data << 1) | 1 ;
+		else if ((levelA == MARK ) && (levelB == SPACE))  data = (data << 1) | 0 ;
+		else                                              return false ;
+	}
+
+	// Success
+	results->bits        = nbits;
+	results->value       = data;
+	results->decode_type = RC5;
+	return true;
+}
+#endif
+
+//+=============================================================================
+// RRRR    CCCC   6666
+// R   R  C      6
+// RRRR   C      6666
+// R  R   C      6   6
+// R   R   CCCC   666
+//
+// NB : Caller needs to take care of flipping the toggle bit
+//
+#define MIN_RC6_SAMPLES      1
+#define RC6_HDR_MARK      2666
+#define RC6_HDR_SPACE      889
+#define RC6_T1             444
+#define RC6_RPT_LENGTH   46000
+
+#if SEND_RC6
+void  IRsend::sendRC6 (unsigned long data,  int nbits)
+{
+	// Set IR carrier frequency
+	enableIROut(36);
+
+	// Header
+	mark(RC6_HDR_MARK);
+	space(RC6_HDR_SPACE);
+
+	// Start bit
+	mark(RC6_T1);
+	space(RC6_T1);
+
+	// Data
+	for (unsigned long  i = 1, mask = 1UL << (nbits - 1);  mask;  i++, mask >>= 1) {
+		// The fourth bit we send is a "double width trailer bit"
+		int  t = (i == 4) ? (RC6_T1 * 2) : (RC6_T1) ;
+		if (data & mask) {
+			mark(t);
+			space(t);
+		} else {
+			space(t);
+			mark(t);
+		}
+	}
+
+	space(0);  // Always end with the LED off
+}
+#endif
+
+//+=============================================================================
+#if DECODE_RC6
+bool  IRrecv::decodeRC6 (decode_results *results)
+{
+	int   nbits;
+	long  data   = 0;
+	int   used   = 0;
+	int   offset = 1;  // Skip first space
+
+	if (results->rawlen < MIN_RC6_SAMPLES)  return false ;
+
+	// Initial mark
+	if (!MATCH_MARK(results->rawbuf[offset++],  RC6_HDR_MARK))   return false ;
+	if (!MATCH_SPACE(results->rawbuf[offset++], RC6_HDR_SPACE))  return false ;
+
+	// Get start bit (1)
+	if (getRClevel(results, &offset, &used, RC6_T1) != MARK)   return false ;
+	if (getRClevel(results, &offset, &used, RC6_T1) != SPACE)  return false ;
+
+	for (nbits = 0;  offset < results->rawlen;  nbits++) {
+		int  levelA, levelB;  // Next two levels
+
+		levelA = getRClevel(results, &offset, &used, RC6_T1);
+		if (nbits == 3) {
+			// T bit is double wide; make sure second half matches
+			if (levelA != getRClevel(results, &offset, &used, RC6_T1)) return false;
+		}
+
+		levelB = getRClevel(results, &offset, &used, RC6_T1);
+		if (nbits == 3) {
+			// T bit is double wide; make sure second half matches
+			if (levelB != getRClevel(results, &offset, &used, RC6_T1)) return false;
+		}
+
+		if      ((levelA == MARK ) && (levelB == SPACE))  data = (data << 1) | 1 ;  // inverted compared to RC5
+		else if ((levelA == SPACE) && (levelB == MARK ))  data = (data << 1) | 0 ;  // ...
+		else                                              return false ;            // Error
+	}
+
+	// Success
+	results->bits        = nbits;
+	results->value       = data;
+	results->decode_type = RC6;
+	return true;
+}
+#endif