ir_NEC.cpp

00001 #include "IRremote.h"
00002 #include "IRremoteInt.h"
00003 
00004 //==============================================================================
00005 //                           N   N  EEEEE   CCCC
00006 //                           NN  N  E      C
00007 //                           N N N  EEE    C
00008 //                           N  NN  E      C
00009 //                           N   N  EEEEE   CCCC
00010 //==============================================================================
00011 
00012 #define NEC_BITS          32
00013 #define NEC_HDR_MARK    9000
00014 #define NEC_HDR_SPACE   4500
00015 #define NEC_BIT_MARK     560
00016 #define NEC_ONE_SPACE   1690
00017 #define NEC_ZERO_SPACE   560
00018 #define NEC_RPT_SPACE   2250
00019 
00020 //+=============================================================================
00021 #if SEND_NEC
00022 void  IRsend::sendNEC (unsigned long data,  int nbits)
00023 {
00024    // Set IR carrier frequency
00025    enableIROut(38);
00026 
00027    // Header
00028    mark(NEC_HDR_MARK);
00029    space(NEC_HDR_SPACE);
00030 
00031    // Data
00032    for (unsigned long  mask = 1UL << (nbits - 1);  mask;  mask >>= 1) {
00033       if (data & mask) {
00034          mark(NEC_BIT_MARK);
00035          space(NEC_ONE_SPACE);
00036       } else {
00037          mark(NEC_BIT_MARK);
00038          space(NEC_ZERO_SPACE);
00039       }
00040    }
00041 
00042    // Footer
00043    mark(NEC_BIT_MARK);
00044    space(0);  // Always end with the LED off
00045 }
00046 #endif
00047 
00048 //+=============================================================================
00049 // NECs have a repeat only 4 items long
00050 //
00051 #if DECODE_NEC
00052 bool  IRrecv::decodeNEC (decode_results *results)
00053 {
00054    long  data   = 0;  // We decode in to here; Start with nothing
00055    int   offset = 1;  // Index in to results; Skip first entry!?
00056 
00057    // Check header "mark"
00058    if (!MATCH_MARK(results->rawbuf[offset], NEC_HDR_MARK))  return false ;
00059    offset++;
00060 
00061    // Check for repeat
00062    /*if ( (irparams.rawlen == 4)
00063        && MATCH_SPACE(results->rawbuf[offset  ], NEC_RPT_SPACE)
00064        && MATCH_MARK (results->rawbuf[offset+1], NEC_BIT_MARK )
00065       ) {
00066       results->bits        = 0;
00067       results->value       = REPEAT;
00068       results->decode_type = NEC;
00069       return true;
00070    }
00071    */
00072 
00073    // Check we have enough data
00074    if (irparams.rawlen < (2 * NEC_BITS) + 4)  return false ;
00075 
00076    // Check header "space"
00077    if (!MATCH_SPACE(results->rawbuf[offset], NEC_HDR_SPACE))  return false ;
00078    offset++;
00079 
00080    int forInverse[32] = {0};
00081    int j = 31;
00082    // Build the data
00083    for (int i = 0;  i < NEC_BITS;  i++) {
00084       // Check data "mark"
00085       if (!MATCH_MARK(results->rawbuf[offset], NEC_BIT_MARK))  return false ;
00086       offset++;
00087         // Suppend this bit
00088       if      (MATCH_SPACE(results->rawbuf[offset], NEC_ONE_SPACE ))  
00089          forInverse[i] = 1;
00090       else if (MATCH_SPACE(results->rawbuf[offset], NEC_ZERO_SPACE)) 
00091          forInverse[i] = 0;
00092       else  return false ;
00093       offset++;
00094       
00095    }
00096    
00097 
00098    for(int j = 0; j < 8; j++){         // 
00099       data = (data << 1) | forInverse[j];
00100    }
00101    for(int j = 8; j < 16; j++){      // 
00102       data = (data << 1) | forInverse[j];
00103    }
00104    for(int j = 23; j > 15; j--){      // 
00105       data = (data << 1) | forInverse[j];
00106    }   
00107    for(int j = 31; j > 23; j--){      // 
00108       data = (data << 1) | forInverse[j];
00109    }   
00110 
00111    
00112    
00113 
00114    // Success
00115    results->bits        = NEC_BITS;
00116    results->value       = data;
00117    results->decode_type = NEC;
00118 
00119    return true;
00120 }
00121 #endif