Updated AFSK with print routine, use new delay line. AX25 receive tune to APRS.

AFSK.cpp

@@ -194,26 +194,25 @@ bool AFSK::HDLCDecode::hdlcParse(bool bit, SimpleFIFO<uint8_t,HAMSHIELD_AFSK_RX_
   return ret;
 }
 
-#define FASTRING_SIZE 4
-#define FASTRING_MASK (FASTRING_SIZE-1)
 template <typename T, int size>
 class FastRing {
 private:
-  T ring[FASTRING_SIZE];
+  T ring[size];
   uint8_t position;
 public:
   FastRing(): position(0) {}
   inline void write(T value) {
-    ring[(position++) & FASTRING_MASK] = value;
+    ring[(position++) & (size-1)] = value;
   }
   inline T read() const {
-    return ring[position & FASTRING_MASK];
+    return ring[position & (size-1)];
   }
   inline T readn(uint8_t n) const {
-    return ring[(position + (~n+1)) & FASTRING_MASK];
+    return ring[(position + (~n+1)) & (size-1)];
   }
 };
-FastRing<uint8_t,4> delayLine;
+// Create a delay line that's half the length of the bit cycle (-90 degrees)
+FastRing<uint8_t,(T_BIT/2)> delayLine;
 
 // Handle the A/D converter interrupt (hopefully quickly :)
 void AFSK::Decoder::process(int8_t curr_sample) {
@@ -269,7 +268,6 @@ bool AFSK::Decoder::read() {
   while(rx_fifo.count()) {
     // Grab the character
     char c = rx_fifo.dequeue();
-    
     bool escaped = false;
     if(c == HDLC_ESCAPE) { // We received an escaped byte, mark it
       escaped = true;
@@ -312,10 +310,10 @@ bool AFSK::Decoder::read() {
               if((currentPacket->getByte() & 0x1) == 0x1) { // Found a byte with LSB set
                 // which marks the final address payload
                 // next two bytes should be the control/PID
-                if(currentPacket->getByte() == 0x03 && currentPacket->getByte() == 0xf0) {
+                //if(currentPacket->getByte() == 0x03 && currentPacket->getByte() == 0xf0) {
                   filtered = true;
                   break; // Found it
-                }
+                //}
               }
             }
             
@@ -520,12 +518,36 @@ size_t AFSK::Packet::appendCallsign(const char *callsign, uint8_t ssid, bool fin
   appendFCS(ssidField);
 }
 
+void AFSK::Packet::print(Stream *s) {
+  uint8_t i;
+  // Second 6 bytes are source callsign
+  for(i=7; i<13; i++) {
+    s->write(*(dataPtr+i)>>1);
+  }
+  // SSID
+  s->write('-');
+  s->print((*(dataPtr+13) >> 1) & 0xF);
+  s->print(" -> ");
+  // First 6 bytes are destination callsign
+  for(i=0; i<6; i++) {
+    s->write(*(dataPtr+i)>>1);
+  }
+  // SSID
+  s->write('-');
+  s->print((*(dataPtr+6) >> 1) & 0xF);
+  // Control/PID next two bytes
+  // Skip those, print payload
+  for(i = 15; i<len; i++) {
+    s->write(*(dataPtr+i));
+  }
+}
+
 // Determine what we want to do on this ADC tick.
 void AFSK::timer() {
   if(encoder.isSending())
     encoder.process();
   else
-    decoder.process(ADCH - 128);
+    decoder.process(((int8_t)(ADCH - 128)));
 }
 
 void AFSK::start(DDS *dds) {

AFSK.h

@@ -111,6 +111,8 @@ public:
     inline bool crcOK() {
       return (fcs == 0xF0B8);
     }
+    
+    void print(Stream *s);
   private:
 #ifdef PACKET_PREALLOCATE
     uint8_t dataPtr[128];

examples/AX25Receive/AX25Receive.ino

@@ -2,29 +2,44 @@
 
 #include <HamShield.h>
 #include <Wire.h>
+//#include <LiquidCrystal_I2C.h>
+
+//LiquidCrystal_I2C lcd(0x27,16,2);
 
 HamShield radio;
 DDS dds;
+volatile uint8_t adcMax=0, adcMin=255;
 
 void setup() {
   Serial.begin(9600);
   Wire.begin();
   pinMode(2, OUTPUT);
   pinMode(3, OUTPUT);
-  
+  /*lcd.init();
+  lcd.setCursor(0,0);
+  lcd.print(F("RSSI:"));
+  lcd.setCursor(0,1);
+  lcd.print(F("ADC:"));*/
   Serial.println(F("Radio test connection"));
   Serial.println(radio.testConnection(), DEC);
   Serial.println(F("Initialize"));
   delay(100);
   radio.initialize();
+  radio.frequency(144390);
+  radio.setVHF();
+  radio.setSQOff();
+  I2Cdev::writeWord(A1846S_DEV_ADDR_SENLOW, 0x30, 0x06);
+  I2Cdev::writeWord(A1846S_DEV_ADDR_SENLOW, 0x30, 0x26);
+  I2Cdev::writeWord(A1846S_DEV_ADDR_SENLOW, 0x44, 0b11111111);
   Serial.println(F("Frequency"));
   delay(100);
-//  radio.setVHF();
-//  radio.setRfPower(0);
-//  radio.setModeReceive();
-  radio.setVolume1(0xFF);
-  radio.setVolume2(0xFF);
-  radio.frequency(145050);
+  Serial.print(F("Squelch(H/L): "));
+  Serial.print(radio.getSQHiThresh());
+  Serial.print(F(" / "));
+  Serial.println(radio.getSQLoThresh());
+  radio.setModeReceive();
+  Serial.print(F("RX? "));
+  Serial.println(radio.getRX());
   Serial.println(F("DDS Start"));
   delay(100);
   dds.start();
@@ -35,26 +50,38 @@ void setup() {
   pinMode(11, INPUT); // Bodge for now, as pin 3 is hotwired to pin 11
   delay(100);
   dds.setAmplitude(255);
+  //lcd.backlight();
 }
 
 uint32_t last = 0;
 void loop() {
    if(radio.afsk.decoder.read() || radio.afsk.rxPacketCount()) {
       // A true return means something was put onto the packet FIFO
-      Serial.println("Packet");
       // If we actually have data packets in the buffer, process them all now
       while(radio.afsk.rxPacketCount()) {
         AFSK::Packet *packet = radio.afsk.getRXPacket();
+        Serial.print(F("Packet: "));
         if(packet) {
-          for(unsigned short i = 0; i < packet->len; ++i)
-            Serial.write((uint8_t)packet->getByte());
+          packet->print(&Serial);
           AFSK::PacketBuffer::freePacket(packet);
         }
       }
+      Serial.println("");
     }
-    /*if(last < millis()) {
-      Serial.println(radio.readRSSI());
-      last = millis()+1000;
+/*    if(last < millis()) {
+      uint16_t buf;
+      lcd.setCursor(6,0);
+      lcd.print(radio.readRSSI());
+      lcd.print(F("  "));
+      lcd.setCursor(6,1);
+      lcd.print(adcMax);
+      lcd.print(F(" / "));
+      lcd.print(adcMin);
+      lcd.print(F("  "));
+      lcd.setCursor(11,0);
+      lcd.print(radio.afsk.decoder.isReceiving());
+      adcMin=255; adcMax=0;
+      last = millis()+100;
     }*/
 }
 
@@ -74,6 +101,12 @@ ISR(ADC_vect) {
   PORTD |= _BV(2); // Diagnostic pin (D2)
   //dds.clockTick();
   radio.afsk.timer();
+  if(ADCH>adcMax) {
+    adcMax = ADCH;
+  }
+  if(ADCH<adcMin) {
+    adcMin = ADCH;
+  }
   PORTD &= ~(_BV(2)); // Pin D2 off again
 }