Revert 9888726..0920f69

This rolls back to commit 9888726.

Author: ezefranca

.DS_Store

@@ -1,4 +1,4 @@
 language: objective-c
 before_install:
-    - cd Example
-script: xcodebuild -workspace EFArduinoFSK.xcworkspace -scheme EFArduinoFSK -sdk iphonesimulator ONLY_ACTIVE_ARCH=NO
+    - cd FSK-Demo
+script: xcodebuild -workspace FSK-Demo.xcworkspace -scheme FSK-Demo -sdk iphonesimulator ONLY_ACTIVE_ARCH=NO

.travis.yml

@@ -0,0 +1,27 @@
+#include <SoftModem.h>
+SoftModem modem;
+int dat;
+ 
+void setup()
+{
+  modem.begin();
+  Serial.begin(115200);
+  pinMode(13,OUTPUT);
+}
+void loop()
+{
+  if(modem.available())
+  {
+    dat = modem.read();
+    if(dat == 'C')
+    {
+      Serial.write('Y');
+      digitalWrite(13,HIGH);
+    }
+    else
+    {
+      Serial.write('N');
+      digitalWrite(13,LOW);     
+    }
+  }
+}

Arduino-SoftModem/Receiver.ino

@@ -0,0 +1,309 @@
+#include "SoftModem.h"
+
+#define TX_PIN      (3)
+#define RX_PIN1     (6)  // AIN0
+#define RX_PIN2     (7)  // AIN1
+
+SoftModem *SoftModem::activeObject = 0;
+
+SoftModem::SoftModem() {
+}
+
+SoftModem::~SoftModem() {
+	end();
+}
+
+#if F_CPU == 16000000
+#if SOFT_MODEM_BAUD_RATE <= 126
+  #define TIMER_CLOCK_SELECT       (7)
+  #define MICROS_PER_TIMER_COUNT   (clockCyclesToMicroseconds(1024))
+#elif SOFT_MODEM_BAUD_RATE <= 315
+  #define TIMER_CLOCK_SELECT       (6)
+  #define MICROS_PER_TIMER_COUNT   (clockCyclesToMicroseconds(256))
+#elif SOFT_MODEM_BAUD_RATE <= 630
+  #define TIMER_CLOCK_SELECT       (5)
+  #define MICROS_PER_TIMER_COUNT   (clockCyclesToMicroseconds(128))
+#elif SOFT_MODEM_BAUD_RATE <= 1225
+  #define TIMER_CLOCK_SELECT       (4)
+  #define MICROS_PER_TIMER_COUNT   (clockCyclesToMicroseconds(64))
+#else
+  #define TIMER_CLOCK_SELECT       (3)
+  #define MICROS_PER_TIMER_COUNT   (clockCyclesToMicroseconds(32))
+#endif
+#else
+#if SOFT_MODEM_BAUD_RATE <= 126
+  #define TIMER_CLOCK_SELECT       (6)
+  #define MICROS_PER_TIMER_COUNT   (clockCyclesToMicroseconds(256))
+#elif SOFT_MODEM_BAUD_RATE <= 315
+  #define TIMER_CLOCK_SELECT       (5)
+  #define MICROS_PER_TIMER_COUNT   (clockCyclesToMicroseconds(128))
+#elif SOFT_MODEM_BAUD_RATE <= 630
+  #define TIMER_CLOCK_SELECT       (4)
+  #define MICROS_PER_TIMER_COUNT   (clockCyclesToMicroseconds(64))
+#else
+  #define TIMER_CLOCK_SELECT       (3)
+  #define MICROS_PER_TIMER_COUNT   (clockCyclesToMicroseconds(32))
+#endif
+#endif
+
+#define BIT_PERIOD             (1000000/SOFT_MODEM_BAUD_RATE)
+#define HIGH_FREQ_MICROS       (1000000/SOFT_MODEM_HIGH_FREQ)
+#define LOW_FREQ_MICROS        (1000000/SOFT_MODEM_LOW_FREQ)
+
+#define HIGH_FREQ_CNT          (BIT_PERIOD/HIGH_FREQ_MICROS)
+#define LOW_FREQ_CNT           (BIT_PERIOD/LOW_FREQ_MICROS)
+
+#define MAX_CARRIR_BITS        (40000/BIT_PERIOD) // 40ms
+
+#define TCNT_BIT_PERIOD        (BIT_PERIOD/MICROS_PER_TIMER_COUNT)
+#define TCNT_HIGH_FREQ         (HIGH_FREQ_MICROS/MICROS_PER_TIMER_COUNT)
+#define TCNT_LOW_FREQ          (LOW_FREQ_MICROS/MICROS_PER_TIMER_COUNT)
+
+#define TCNT_HIGH_TH_L         (TCNT_HIGH_FREQ * 0.80)
+#define TCNT_HIGH_TH_H         (TCNT_HIGH_FREQ * 1.15)
+#define TCNT_LOW_TH_L          (TCNT_LOW_FREQ * 0.85)
+#define TCNT_LOW_TH_H          (TCNT_LOW_FREQ * 1.20)
+
+#if SOFT_MODEM_DEBUG_ENABLE
+static volatile uint8_t *_portLEDReg;
+static uint8_t _portLEDMask;
+#endif
+
+enum { START_BIT = 0, DATA_BIT = 8, STOP_BIT = 9, INACTIVE = 0xff };
+
+void SoftModem::begin(void)
+{
+	pinMode(RX_PIN1, INPUT);
+	digitalWrite(RX_PIN1, LOW);
+
+	pinMode(RX_PIN2, INPUT);
+	digitalWrite(RX_PIN2, LOW);
+
+	pinMode(TX_PIN, OUTPUT);
+	digitalWrite(TX_PIN, LOW);
+
+	_txPortReg = portOutputRegister(digitalPinToPort(TX_PIN));
+	_txPortMask = digitalPinToBitMask(TX_PIN);
+
+#if SOFT_MODEM_DEBUG_ENABLE
+	_portLEDReg = portOutputRegister(digitalPinToPort(13));
+	_portLEDMask = digitalPinToBitMask(13);
+    pinMode(13, OUTPUT);
+#endif
+
+	_recvStat = INACTIVE;
+	_recvBufferHead = _recvBufferTail = 0;
+
+	SoftModem::activeObject = this;
+
+	_lastTCNT = TCNT2;
+	_lastDiff = _lowCount = _highCount = 0;
+
+	TCCR2A = 0;
+	TCCR2B = TIMER_CLOCK_SELECT;
+	ACSR   = _BV(ACIE) | _BV(ACIS1);
+	DIDR1  = _BV(AIN1D) | _BV(AIN0D); // digital port off
+}
+
+void SoftModem::end(void)
+{
+	ACSR   &= ~(_BV(ACIE));
+	TIMSK2 &= ~(_BV(OCIE2A));
+	DIDR1  &= ~(_BV(AIN1D) | _BV(AIN0D));
+	SoftModem::activeObject = 0;
+}
+
+void SoftModem::demodulate(void)
+{
+	uint8_t t = TCNT2;
+	uint8_t diff;
+	
+	if(TIFR2 & _BV(TOV2)){
+		TIFR2 |= _BV(TOV2);
+		diff = (255 - _lastTCNT) + t + 1;
+	}
+	else{
+		diff = t - _lastTCNT;
+	}
+	
+	if(diff < (uint8_t)(TCNT_HIGH_TH_L))				// Noise?
+		return;
+	
+	_lastTCNT = t;
+	
+	if(diff > (uint8_t)(TCNT_LOW_TH_H))
+		return;
+	
+//	_lastDiff = (diff >> 1) + (diff >> 2) + (_lastDiff >> 2);
+    _lastDiff = diff;
+	
+	if(_lastDiff >= (uint8_t)(TCNT_LOW_TH_L)){
+		_lowCount += _lastDiff;
+		if((_recvStat == INACTIVE) && (_lowCount >= (uint8_t)(TCNT_BIT_PERIOD * 0.5))){ // maybe Start-Bit
+			_recvStat  = START_BIT;
+			_highCount = 0;
+			_recvBits  = 0;
+			OCR2A      = t + (uint8_t)(TCNT_BIT_PERIOD) - _lowCount; // 1 bit period after detected
+			TIFR2     |= _BV(OCF2A);
+			TIMSK2    |= _BV(OCIE2A);
+		}
+	}
+	else if(_lastDiff <= (uint8_t)(TCNT_HIGH_TH_H)){
+		_highCount += _lastDiff;
+		if((_recvStat == INACTIVE) && (_highCount >= (uint8_t)(TCNT_BIT_PERIOD))){
+			_lowCount = _highCount = 0;
+		}
+	}
+}
+
+ISR(ANALOG_COMP_vect)
+{
+	SoftModem::activeObject->demodulate();
+}
+
+void SoftModem::recv(void)
+{
+	uint8_t high;
+	if(_highCount > _lowCount){
+ 		if(_highCount >= (uint8_t)TCNT_BIT_PERIOD)
+ 			_highCount -= (uint8_t)TCNT_BIT_PERIOD;
+		else
+			_highCount = 0;
+		high = 0x80;
+	}
+	else{
+ 		if(_lowCount >= (uint8_t)TCNT_BIT_PERIOD)
+ 			_lowCount -= (uint8_t)TCNT_BIT_PERIOD;
+ 		else
+			_lowCount = 0;
+		high = 0x00;
+	}
+	
+	if(_recvStat == START_BIT){	// Start bit
+		if(!high){
+			_recvStat++;
+		}else{
+			goto end_recv;
+		}
+	}
+	else if(_recvStat <= DATA_BIT) { // Data bits
+		_recvBits >>= 1;
+		_recvBits |= high;
+		_recvStat++;
+	}
+	else if(_recvStat == STOP_BIT){	// Stop bit
+		uint8_t new_tail = (_recvBufferTail + 1) & (SOFT_MODEM_RX_BUF_SIZE - 1);
+		if(new_tail != _recvBufferHead){
+			_recvBuffer[_recvBufferTail] = _recvBits;
+			_recvBufferTail = new_tail;
+		}
+		goto end_recv;
+	}
+	else{
+	end_recv:
+		_recvStat = INACTIVE;
+		TIMSK2 &= ~_BV(OCIE2A);
+	}
+}
+
+ISR(TIMER2_COMPA_vect)
+{
+	OCR2A += (uint8_t)TCNT_BIT_PERIOD;
+	SoftModem::activeObject->recv();
+#if SOFT_MODEM_DEBUG_ENABLE
+	*_portLEDReg ^= _portLEDMask;
+#endif  
+}
+
+int SoftModem::available()
+{
+	return (_recvBufferTail + SOFT_MODEM_RX_BUF_SIZE - _recvBufferHead) & (SOFT_MODEM_RX_BUF_SIZE - 1);
+}
+
+int SoftModem::read()
+{
+	if(_recvBufferHead == _recvBufferTail)
+		return -1;
+	int d = _recvBuffer[_recvBufferHead];
+	_recvBufferHead = (_recvBufferHead + 1) & (SOFT_MODEM_RX_BUF_SIZE - 1);
+	return d;
+}
+
+int SoftModem::peek()
+{
+	if(_recvBufferHead == _recvBufferTail)
+		return -1;
+	return _recvBuffer[_recvBufferHead];
+}
+
+void SoftModem::flush()
+{
+	_recvBufferHead = _recvBufferTail = 0;
+}
+
+void SoftModem::modulate(uint8_t b)
+{
+	uint8_t cnt,tcnt,tcnt2;
+	if(b){
+		cnt = (uint8_t)(HIGH_FREQ_CNT);
+		tcnt2 = (uint8_t)(TCNT_HIGH_FREQ / 2);
+		tcnt = (uint8_t)(TCNT_HIGH_FREQ) - tcnt2;
+	}else{
+		cnt = (uint8_t)(LOW_FREQ_CNT);
+		tcnt2 = (uint8_t)(TCNT_LOW_FREQ / 2);
+		tcnt = (uint8_t)(TCNT_LOW_FREQ) - tcnt2;
+	}
+	do {
+		cnt--;
+		{
+			OCR2B += tcnt;
+			TIFR2 |= _BV(OCF2B);
+			while(!(TIFR2 & _BV(OCF2B)));
+		}
+		*_txPortReg ^= _txPortMask;
+		{
+			OCR2B += tcnt2;
+			TIFR2 |= _BV(OCF2B);
+			while(!(TIFR2 & _BV(OCF2B)));
+		}
+		*_txPortReg ^= _txPortMask;
+	} while (cnt);
+}
+
+//  Brief carrier tone before each transmission
+//  1 start bit (LOW)
+//  8 data bits, LSB first
+//  1 stop bit (HIGH)
+//  ...
+//  1 push bit (HIGH)
+
+size_t SoftModem::write(const uint8_t *buffer, size_t size)
+{
+    uint8_t cnt = ((micros() - _lastWriteTime) / BIT_PERIOD) + 1;
+    if(cnt > MAX_CARRIR_BITS)
+        cnt = MAX_CARRIR_BITS;
+    for(uint8_t i = 0; i<cnt; i++)
+        modulate(HIGH);
+    size_t n = size;
+    while (size--) {
+        uint8_t data = *buffer++;
+        modulate(LOW);							 // Start Bit
+        for(uint8_t mask = 1; mask; mask <<= 1){ // Data Bits
+            if(data & mask){
+                modulate(HIGH);
+            }
+            else{
+                modulate(LOW);
+            }
+        }
+        modulate(HIGH);				// Stop Bit
+    }
+	modulate(HIGH);				// Push Bit
+    _lastWriteTime = micros();
+    return n;
+}
+
+size_t SoftModem::write(uint8_t data)
+{
+    return write(&data, 1);
+}