Increased max frame length. Other minor tweaks.

hardware/AFSK.c

@@ -379,7 +379,7 @@ void AFSK_adc_isr(Afsk *afsk, int8_t currentSample) {
     // First we bitshift everything 1 left
     afsk->sampledBits <<= 1;
     // And then add the sampled bit to our delay line
-    afsk->sampledBits |= (afsk->iirY[1] > 0) ? 1 : 0;
+    afsk->sampledBits |= (afsk->iirY[1] > 0) ? 0 : 1;
 
     // Put the current raw sample in the delay FIFO
     fifo_push(&afsk->delayFifo, currentSample);
@@ -464,7 +464,7 @@ void AFSK_adc_isr(Afsk *afsk, int8_t currentSample) {
         /////////////////////////////////////////////////
 
         // Now we can pass the actual bit to the HDLC parser.
-        // We are using NRZ coding, so if 2 consecutive bits
+        // We are using NRZ-S coding, so if 2 consecutive bits
         // have the same value, we have a 1, otherwise a 0.
         // We use the TRANSITION_FOUND function to determine this.
         //
@@ -476,7 +476,7 @@ void AFSK_adc_isr(Afsk *afsk, int8_t currentSample) {
         // not be able to synchronize our phase to the transmitter
         // and would start experiencing "bit slip".
         //
-        // By combining bit-stuffing with NRZ coding, we ensure
+        // By combining bit-stuffing with NRZ-S coding, we ensure
         // that the signal will regularly make transitions
         // that we can use to synchronize our phase.
         //

hardware/AFSK.h

@@ -52,11 +52,16 @@ inline static uint8_t sinSample(uint16_t i) {
 #define SAMPLESPERBIT (SAMPLERATE / BITRATE)
 #define PHASE_INC    1                              // Nudge by an eigth of a sample each adjustment
 
-#if BITRATE == 960
+#if BITRATE == 300
+    #define FILTER_CUTOFF 600
+    #define MARK_FREQ  1600
+    #define SPACE_FREQ 1800
+    #define PHASE_BITS   10                         // How much to increment phase counter each sample
+#elif BITRATE == 960
     #define FILTER_CUTOFF 600
     #define MARK_FREQ  960
     #define SPACE_FREQ 1600
-    #define PHASE_BITS   10                         // How much to increment phase counter each sample
+    #define PHASE_BITS   10
 #elif BITRATE == 1200
     #define FILTER_CUTOFF 600
     #define MARK_FREQ  1200

protocol/AX25.h

@@ -7,7 +7,7 @@
 
 #define AX25_MIN_FRAME_LEN 18
 #ifndef CUSTOM_FRAME_SIZE
-    #define AX25_MAX_FRAME_LEN 620
+    #define AX25_MAX_FRAME_LEN 792
 #else
     #define AX25_MAX_FRAME_LEN CUSTOM_FRAME_SIZE
 #endif