Erfahrungen und Erfahrungsaustausch mit Arexx Robot-Arm-mini

[Dirk]

@Ralf:
Ok, ich würde den RC5-Code in die Lib in die ISR(TIMER2_COMP_vect), also in den 100us Interrupt einklinken.
Beispiel:

// Dies VOR die ISR:
volatile RC5data_t RC5_newdata;  // Decoded RC5 data
 
// Dies hier IN die ISR (ans Ende!):
// ----------------------------------------------------------------------------
 // RC5 reception code (adapted for Robot Arm from Asuro Lib):
 #define F_ISR   10e3   // 10kHz (100µs)
 #define RC5_TIME   1.778e-3  // 1.778ms
 #define RC5_SAMPLES_PER_BIT_MIN  (uint8_t)(F_ISR * RC5_TIME * 0.4)
 #define RC5_SAMPLES_PER_BIT_EARLY (uint8_t)(F_ISR * RC5_TIME * 0.75)
 #define RC5_SAMPLES_PER_BIT_LATE (uint8_t)(F_ISR * RC5_TIME * 1.25)
 #define RC5_PAUSE_SAMPLES   250 // 25ms (RC5 pause: 88.889ms)
 static uint8_t RC5_lastsample = 0;  // Last read sample
 static uint8_t RC5_timecounter = 0;  // Bit time counter
 static uint16_t RC5_bitstream = 0;  // RC5 bit stream
 static uint8_t RC5_bitcounter = 0;  // RC5 bit counter
 uint8_t sample = 1;
 if(PIND & RESERVE_PD7)      // Read RC5 input (PD7)
  sample = 0;
 if(RC5_timecounter < 255)    // Time counter limited to 8 bit
  RC5_timecounter++;
 if(RC5_lastsample != sample) {   // Detect edges
  if(RC5_timecounter <= RC5_SAMPLES_PER_BIT_MIN)
   RC5_bitcounter = 0;    // Edge to early
  else {
   if(RC5_bitcounter == 0) {  // RC5 start bit
    if((sample == 1)
     && (RC5_timecounter > RC5_PAUSE_SAMPLES)) {
     RC5_bitstream = 1;  // Store start bit
     RC5_bitcounter++;
    }
    else
     RC5_bitstream = 0;  // To long pause: Error
    RC5_timecounter = 0;  // Reset bit time counter
   }
   else {       // RC5 bits 2..14:
    if(RC5_timecounter >= RC5_SAMPLES_PER_BIT_EARLY) {
     if(RC5_timecounter <= RC5_SAMPLES_PER_BIT_LATE) {
      RC5_bitstream = (RC5_bitstream << 1) | sample;
      RC5_bitcounter++;
     }
     else
      RC5_bitcounter = 0; // To late: Error
     RC5_timecounter = 0; // Reset bit time counter
    }
   }
  }
 }
 else {
  if(RC5_timecounter > RC5_SAMPLES_PER_BIT_LATE) { // No edge in bit?
   if(RC5_bitcounter == 14) {  // All 14 RC5 bits read?
    RC5_newdata.data = RC5_bitstream;
    RC5_Ready = 1;    // New data received!
   }
   RC5_bitcounter = 0;    // Reset RC5 bit counter
  }
 }
 RC5_lastsample = sample;    // Store sample in sample buffer
// ----------------------------------------------------------------------------

Dazu müßte man im Header der Lib die Variablen definieren:

typedef union {
 uint16_t data;     // RC5 data structure (14 bits):
 struct {
  unsigned key_code : 6; // RC5 key code        C0..C5
  unsigned device  : 5; // RC5 device address  A0..A4
  unsigned toggle_bit : 1; // RC5 toggle bit      F
  unsigned key_codeC6 : 1; // RC5 key code bit 6  !(C6)
  unsigned start_bit : 1; // RC5 start bit       1
  unsigned notused : 2;
 };
} RC5data_t;
// RC5data_t RC5_data;     // Received RC5 data
volatile uint8_t RC5_Ready;   // RC5 data ready (true/false)

Probier das mal! Wenn RC5_Ready true (1) wird, wurden Daten in RC5_newdata empfangen. Das Hauptprogramm müßte also RC5_Ready ständig pollen (z.B. in einer task_RC5 in der Hauptschleife). Nachdem die Daten aus RC5_newdata gelesen wurden, muss man noch RC5_Ready false setzen, damit die nächsten Daten empfangen werden können.
Als Eingangspin habe ich PD7 genommen.