Conception d’un récepteur de démarrage infrarouge

// furnished to do so, subject to the following conditions :

//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//-----------------------------------------------------------------------------
//
// Pobot Robotic Sophia Antipolis
//
// Code compatible IR SONY remote control
// 40 KHz main freq.
// decode first 4 characters
// use :
// - key 9 : to re-program OFF key
// - key 0 : to re-program ON key
//
// Note : Do not forget to “burn bootloader” with clock set
// to “internal at 8MHz” before any programing. Else the timer setting
//. Will be incorrect, and the decoder will not decode correctly.
//
//-----------------------------------------------------------------------------

#include <EEPROM.h>

#define SIGNAL_START_PIN PB4
#define IR_SENSOR_PIN PB3

#define EEPROM_ADDR_KEY_ON 0
#define EEPROM_ADDR_KEY_OFF 1

static volatile uint8_t code_len, code ;

enum KEY_VALUES { OFF, ON, REPROG_OFF, REPROG_ON} ;
static volatile enum KEY_VALUES key[4] ;
enum IR_STATES { WAIT_START, ACQ} ;
static volatile enum IR_STATES ir_state ;

void init_timer() {
// Configure Timer0 at 5kHz (for fuse set as internal clk 8MHz)
TCCR1 = (1 << CTC1) + 5 ; // CTC mode + prescaler PCK/16
// boring part ... look at ATiny datasheet
TCNT1 = 0 ; GTCCR = _BV(PSR1) ;
OCR1A = 99 ; OCR1C = 99 ;
TCNT1 = 0 ; GTCCR = 0 ;
TIMSK = (1 << OCIE1A) ;
// end boring part
}

void code_capture() {
static uint8_t count = 0 ;
if(!digitalRead(IR_SENSOR_PIN)) {
count++ ;
} else {
// Configure Timer0 5kHz. internal at 8MHz
// 0 logic -> ir@0 for 2-3 pulses,
// 1 logic -> 5-6 pulses,
// Start logic -> 11-12 pulses
if(count > 0){
if(ir_state == WAIT_START) {
code_len = 0 ;
if(count >= 11 && count <= 12) {
ir_state = ACQ ;
}
} else {
code_len++ ;
code = code << 1 ; // push
if(count >= 6 && count <= 7)
code++ ;
}
count = 0 ;
}
}
}

void process_msg() {
static char reprog = 0 ;
if(reprog !=0) {
if((code & 0xF) != key[REPROG_OFF] &&
(code & 0xF) != key[REPROG_ON]) {
//noInterrupts() ; // need because we hang the ISR function with long eeprom write and delay
if(reprog == 1) {
key[OFF] = code & 0xF ;
} else {
key[ON] = code & 0xF ;
}
//EEPROM.write(EEPROM_ADDR_KEY_ON, key[ON]) ;
//digitalWrite(SIGNAL_START_PIN, LOW) ;
reprog = 0 ;
for(int x=0 ; x<10 ; x++) {
digitalWrite(SIGNAL_START_PIN, HIGH) ;
delay(10000) ; // to slow down the process a little bit
digitalWrite(SIGNAL_START_PIN, LOW) ;
delay(10000) ;
}
//interrupts() ;
}
} else {
if((code & 0xF) == key[ON]) {
digitalWrite(SIGNAL_START_PIN, HIGH) ;
/* noInterrupts() ; // need because we hang the ISR function with long eeprom write and delay
for(int x=0 ; x<10 ; x++) {
digitalWrite(SIGNAL_START_PIN, HIGH) ;
delay(1000) ;
digitalWrite(SIGNAL_START_PIN, LOW) ;
delay(3000) ;
}
interrupts() ;*/
} else if((code & 0xF) == key[OFF]){
digitalWrite(SIGNAL_START_PIN, LOW) ;
/* noInterrupts() ; // need because we hang the ISR function with long eeprom write and delay
for(int x=0 ; x<10 ; x++) {
digitalWrite(SIGNAL_START_PIN, HIGH) ;
delay(2000) ;
digitalWrite(SIGNAL_START_PIN, LOW) ;
delay(10000) ;
}
interrupts() ;*/
} else if ((code & 0xF) == key[REPROG_OFF]) { // re program mode active
/*noInterrupts() ; // need because we hang the ISR function with long eeprom write and delay
for(int x=0 ; x<4 ; x++) {
digitalWrite(SIGNAL_START_PIN, HIGH) ;
delay(2000) ;
digitalWrite(SIGNAL_START_PIN, LOW) ;
delay(2000) ;
}
interrupts() ;*/
reprog = 1 ;
} else if ((code & 0xF) == key[REPROG_ON]) { // re program mode active
reprog = 2 ;
}
}
}

ISR(TIMER1_COMPA_vect) {
noInterrupts() ;
code_capture() ;
if(code_len == 4) {
ir_state = WAIT_START ;
process_msg() ;
}
interrupts() ;
}

char key_to_code(char key){
char code = 0 ;

for(uint8_t i=0 ; i<4 ; i++) {
code += ((((key+9)%10) >> i) & 0x1) << (3-i) ;
}

return code ;
}

void setup() {
pinMode(IR_SENSOR_PIN, INPUT) ;
digitalWrite(SIGNAL_START_PIN, LOW) ;
pinMode(SIGNAL_START_PIN, OUTPUT) ;

//EEPROM.write(EEPROM_ADDR_KEY_ON, key_to_code(2)) ;
//EEPROM.write(EEPROM_ADDR_KEY_OFF, key_to_code(3)) ;

key[ON] = EEPROM.read(EEPROM_ADDR_KEY_ON) ;
key[OFF] = EEPROM.read(EEPROM_ADDR_KEY_OFF) ;
key[REPROG_OFF] = key_to_code(0) ; // LSB first, so 8 is 1 (code len 4)
key[REPROG_ON] = key_to_code(9) ;

init_timer() ;

ir_state = WAIT_START ;
sei() ; // Enable Int.
}