WIP FSK TX and revised AFSK TX.

tracker/software/Makefile

@@ -175,6 +175,7 @@ CSRC = $(STARTUPSRC) \
 	   pkt/devices/dbguart.c \
 	   pkt/sys/ihex_out.c \
 	   pkt/diagnostics/ax25_dump.c \
+	   pkt/diagnostics/pktevt.c \
 	   pkt/protocols/txhdlc.c \
        \
        main.c \

tracker/software/main.c

@@ -23,13 +23,11 @@ int main(void) {
     /* Start serial channels. */
     pktSerialStart();
 
-    event_listener_t pkt_el;
-
     /* Create packet radio service. */
     if(!pktServiceCreate(PKT_RADIO_1)) {
       TRACE_ERROR("PKT  > Unable to create packet services");
     } else {
-      chEvtRegister(pktGetEventSource(&RPKTD1), &pkt_el, 1);
+      pktEnableEventTrace();
     }
 
 	#if ACTIVATE_USB
@@ -44,40 +42,7 @@ int main(void) {
         #if ACTIVATE_USB
 		if(isUSBactive()) {
 			manageShell();
-			eventmask_t evt = chEvtGetAndClearEvents(EVENT_MASK(1));
+			pktTraceEvents();
-			if(evt) {
-			  eventflags_t flags = chEvtGetAndClearFlags(&pkt_el);
-			  if(flags & EVT_PWM_QUEUE_FULL) {
-			    TRACE_WARN("PKT  > PWM queue full");
-			  }
-              if(flags & EVT_PWM_FIFO_EMPTY) {
-                TRACE_WARN("PKT  > PWM FIFO exhausted");
-              }
-              if(flags & EVT_AX25_NO_BUFFER) {
-                TRACE_WARN("PKT  > AX25 FIFO exhausted");
-              }
-              if(flags & EVT_ICU_SLEEP_TIMEOUT) {
-                TRACE_INFO("PKT  > PWM ICU has entered sleep");
-              }
-              if(flags & EVT_AX25_BUFFER_FULL) {
-                TRACE_WARN("PKT  > AX25 receive buffer full");
-              }
-              if(flags & EVT_DECODER_ERROR) {
-                TRACE_ERROR("PKT  > Decoder error");
-              }
-              if(flags & EVT_PWM_UNKNOWN_INBAND) {
-                TRACE_ERROR("PKT  > Unknown PWM inband flag");
-              }
-              if(flags & EVT_ICU_OVERFLOW) {
-                TRACE_WARN("PKT  > PWM ICU overflow");
-              }
-              if(flags & EVT_PWM_STREAM_TIMEOUT) {
-                TRACE_WARN("PKT  > PWM steam timeout");
-              }
-              if(flags & EVT_PWM_NO_DATA) {
-                TRACE_WARN("PKT  > PWM data not started from radio");
-              }
-			}
 			continue;
 		}
         #endif /* ACTIVATE_USB */

tracker/software/pkt/devices/si446x.c

@@ -1098,6 +1098,23 @@ static uint8_t Si446x_getUpsampledAFSKbits(uint8_t* buf/*, uint32_t blen*/)
     return b;
 }
 
+static void Si446x_upsampleAFSKstream(uint8_t current_byte,
+                                               uint8_t *buf,
+                                               uint8_t upsample_rate) {
+  uint8_t b = 0, i = 0, usr = 0;
+  for(usr = 0; usr < upsample_rate; usr++) {
+    do {
+      // Toggle tone (1200 <> 2200)
+      phase_delta = (current_byte & 1) ? PHASE_DELTA_1200 : PHASE_DELTA_2200;
+      /* Add delta-phase (bit count within SAMPLES_PER_BAUD). */
+      phase += phase_delta;
+      b |= ((phase >> 16) & 1) << i;  // Set modulation bit
+    } while(++i != 8);
+    current_byte >>= (i * 8) / upsample_rate;
+    buf[usr] = b;
+  }
+}
+
 #define SI446X_EVT_AFSK_TX_TIMEOUT      EVENT_MASK(0)
 
 static void Si446x_AFSKtransmitTimeoutI(thread_t *tp) {
@@ -1240,7 +1257,7 @@ THD_FUNCTION(si_fifo_feeder_afsk, arg) {
 }
 
 /*
- *
+ * AFSK transmit manager thread.
  */
 THD_FUNCTION(new_si_fifo_feeder_afsk, arg) {
     packet_t pp = arg;
@@ -1255,27 +1272,17 @@ THD_FUNCTION(new_si_fifo_feeder_afsk, arg) {
 
     chVTObjectInit(&send_timer);
 
-    uint8_t layer0[AFSK_FEEDER_BUFFER_SIZE];
+    //uint8_t layer0[AFSK_FEEDER_BUFFER_SIZE];
 
     TRACE_INFO("SI   > Packet frame bytes %i", pp->frame_len);
 
-    /* TODO: Make this a prepare function.
-     * Create iterator object and complete TX frame.
-     * Insert CRC in radio.c transmit function?
-     */
-
     static tx_iterator_t iterator;
 
     pktStreamIteratorInit(&iterator, pp, false);
 
-    static int32_t data = 0;
+    uint16_t all = pktStreamEncodingIterator(&iterator, NULL, 0);
-    data = pktStreamEncodingIterator(&iterator, layer0, sizeof(layer0));
 
-    TRACE_INFO("SI   > Iterator data count %i, RLL count %i,"
+    TRACE_INFO("SI   > Packet stream bytes %i", all);
-        " out index %i, out bytes %i, out bits %i",
-               data, iterator.rll_count,
-               iterator.out_index, iterator.out_index >> 3,
-               iterator.out_index % 8);
 
 #ifdef TX_ITERATOR_VERIFICATION
     uint8_t layer1[AFSK_FEEDER_BUFFER_SIZE];
@@ -1304,45 +1311,13 @@ THD_FUNCTION(new_si_fifo_feeder_afsk, arg) {
     }
 #endif
 
-    /* Reset TX FIFO in case some remnant unsent data is left there. */
+    TRACE_INFO("SI   > AFSK frame bytes to send %i, upsampled %i",
-    const uint8_t reset_fifo[] = {0x15, 0x01};
+               all, all * SAMPLES_PER_BAUD);
-    Si446x_write(reset_fifo, 2);
-
-    /* Maximum amount of FIFO data when using combined TX+RX (safe size). */
-    uint8_t localBuffer[Si446x_FIFO_COMBINED_SIZE];
-
-    /* Get the FIFO buffer amount currently available. */
-    uint8_t free = Si446x_getTXfreeFIFO();
-
-    /* Calculate chunk size for stream iterator. */
-
-    uint8_t stream_size = free / SAMPLES_PER_BAUD;
-
-    /* Allocate a stream output buffer. */
-    uint8_t stream_out[stream_size];
-
-    TRACE_INFO("SI   > AFSK stream buffer %i @ 0x%x", stream_size, stream_out);
-    /*
-     * Account for all modulation bits (round up to a byte boundary).
-     * Calculate initial FIFO fill.
-     */
-    uint16_t all = data * SAMPLES_PER_BAUD;
-    uint16_t c = 0; /*(all > free) ? free : all;*/
-
-    TRACE_INFO("SI   > AFSK frame bytes to send %i, upsampled %i", data, all);
 
     /*
-     * Start transmission timeout timer.
+     * Initialize variables for up sampler.
-     * If the 446x gets locked up we'll exit TX and release packet object.
+     * TODO: Use an up-sampler object.
      */
-    chVTSet(&send_timer, TIME_S2I(10),
-             (vtfunc_t)Si446x_AFSKtransmitTimeoutI, chThdGetSelfX());
-
-    /* The exit message if all goes well. */
-    msg_t exit_msg = MSG_OK;
-    bool tx_started = false;
-
-    /* Initialize variables for up sampler. */
     phase_delta = PHASE_DELTA_1200;
     phase = 0;
     packet_pos = 0;
@@ -1351,48 +1326,83 @@ THD_FUNCTION(new_si_fifo_feeder_afsk, arg) {
 
     uint8_t lower = Si446x_FIFO_COMBINED_SIZE;
 
-    /* Feed the FIFO while data remains to be sent. */
+    /* The FIFO size required to output one stream byte. */
-    while((all - c) > 0) {
+    uint8_t localBuffer[SAMPLES_PER_BAUD];
-      /* Get TX FIFO free count. */
+    memset(localBuffer, 0, sizeof(localBuffer));
-      uint8_t more = Si446x_getTXfreeFIFO();
 
+    /* The exit message if all goes well. */
+    msg_t exit_msg = MSG_OK;
+    bool tx_started = false;
+
+    /* Reset TX FIFO in case some remnant unsent data is left there. */
+    const uint8_t reset_fifo[] = {0x15, 0x01};
+    Si446x_write(reset_fifo, 2);
+
+    eventmask_t evt = 0;
+
+    /*
+     * Start transmission timeout timer.
+     * If the 446x gets locked up we'll exit TX and release packet object.
+     */
+/*    chVTSet(&send_timer, TIME_S2I(3),
+             (vtfunc_t)Si446x_AFSKtransmitTimeoutI, chThdGetSelfX());*/
+
+    /*
+     * Wait in a timeout event during up-sampled AFSK byte time period.
+     * Time delay allows for ~11 bytes of transmit data from the FIFO.
+     * If no timeout event continue and check for sufficient FIFO space.
+     */
+    while((evt = chEvtWaitAnyTimeout(SI446X_EVT_AFSK_TX_TIMEOUT,
+                           chTimeUS2I(833 * 8 * SAMPLES_PER_BAUD))) == 0) {
+      uint8_t more = Si446x_getTXfreeFIFO();
       /* Update the FIFO low water mark. */
       lower = (more < lower) ? more : lower;
+      if(more < SAMPLES_PER_BAUD)
+        continue;
+#define IT_BYTES 1
+      uint8_t byte[IT_BYTES];
+      uint16_t data = 0;
+      uint16_t count = 0;
+      while(iterator.state != ITERATE_END) {
+        data = pktStreamEncodingIterator(&iterator, byte, IT_BYTES);
 
-      /* If there is more free than we need for send use remainder only. */
+        TRACE_INFO("SI   > Iterator byte 0x%02x, data %i, all %03i, index %03i, "
-      more = (more > (all - c)) ? (all - c) : more;
+            "state %i, HDLC %03i, RLL %02i, data %03i, out index 0x%05x",
+                   byte[0], data, all, ++count, iterator.state,
+                   iterator.hdlc_count, iterator.rll_count,
+                   iterator.data_size, iterator.out_index);
+        chThdSleep(TIME_MS2I(500));
+      }
+      break;
+#if 0
+      if((data = pktStreamEncodingIterator(&iterator, byte, 1)) == 0) {
+         /* All data streamed. */
+         exit_msg = MSG_OK;
+         break;
+      }
+      /* Load the interim buffer and transfer to FIFO. */
+      Si446x_upsampleAFSKstream(byte[0], localBuffer,
+                                        SAMPLES_PER_BAUD);
+      Si446x_writeFIFO(localBuffer, SAMPLES_PER_BAUD); // Write into FIFO
 
-      /* Load the FIFO. */
+      TRACE_INFO("SI   > Transmit AFSK stream byte with FIFO %i", more);
-      for(uint16_t i = 0; i < more; i++)
-          localBuffer[i] = Si446x_getUpsampledAFSKbits(layer0);
-      Si446x_writeFIFO(localBuffer, more); // Write into FIFO
-      c += more;
 
       if(!tx_started) {
         /* Request start of transmission. */
         if(!Si446x_transmit(pp->radio_chan, pp->radio_pwr, all,
                            pp->cca_rssi, TIME_S2I(10))) {
-          /* Transmit start failed. */
-          TRACE_ERROR("SI   > Transmit start failed");
           exit_msg = MSG_RESET;
           break;
         } /* Else. */
-            tx_started = true;
+          tx_started = true;
-      }
-      /*
-       * Wait for a timeout event during up-sampled AFSK byte time period.
-       * Time delay allows for ~11 bytes of transmit data from the FIFO.
-       * If no timeout event go back and load more data to FIFO.
-       */
-      eventmask_t evt = chEvtWaitAnyTimeout(SI446X_EVT_AFSK_TX_TIMEOUT,
-                                 chTimeUS2I(833 * 8 * SAMPLES_PER_BAUD));
-      if(evt) {
-        /* Force 446x out of TX state. */
-        Si446x_setReadyState();
-        exit_msg = MSG_TIMEOUT;
-        break;
       }
+#endif
     } /* End while. */
+    /* Arrive here on break from while or TX timeout. */
+    if(exit_msg != MSG_OK) {
+      /* Force 446x out of TX state. */
+      Si446x_setReadyState();
+    }
     chVTReset(&send_timer);
 
     /*
@@ -1408,7 +1418,7 @@ THD_FUNCTION(new_si_fifo_feeder_afsk, arg) {
     // Free packet object memory
     pktReleaseSendObject(pp);
 
-    TRACE_INFO("SI   > TX FIFO low level %i", lower);
+    TRACE_INFO("SI   > TX FIFO lowest level %i", lower);
 
     /* Exit thread. */
     chThdExit(exit_msg);
@@ -1439,10 +1449,14 @@ void Si446x_sendAFSK(packet_t pp,
 
 #if USE_DYNAMIC_AFSK_TX == TRUE
     afsk_feeder_thd = chThdCreateFromHeap(NULL,
+#ifdef TX_ITERATOR_VERIFICATION
                 THD_WORKING_AREA_SIZE(SI_AFSK_FIFO_FEEDER_WA_SIZE * 2),
+#else
+                THD_WORKING_AREA_SIZE(SI_AFSK_FIFO_FEEDER_WA_SIZE),
+#endif
                 "446x_afsk_tx",
                 NORMALPRIO - 10,
-                si_fifo_feeder_afsk,
+                new_si_fifo_feeder_afsk,
                 pp);
 #else
     // Start/re-start FIFO feeder
@@ -1467,7 +1481,7 @@ void Si446x_sendAFSK(packet_t pp,
       TRACE_ERROR("SI   > Transmit AFSK timeout");
     }
     if(send_msg == MSG_RESET) {
-      TRACE_ERROR("SI   > Transmit AFSK buffer overrun");
+      TRACE_ERROR("SI   > Transmit AFSK failed to start");
     }
     /* Unlock radio. */
     Si446x_unlockRadio(RADIO_TX);

tracker/software/pkt/diagnostics/pktevt.c

@@ -0,0 +1,65 @@
+/*
+    Aerospace Decoder - Copyright (C) 2018 Bob Anderson (VK2GJ)
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+*/
+
+#include "pktconf.h"
+
+event_listener_t pkt_el;
+static bool trace_enabled = false;
+
+
+void pktEnableEventTrace() {
+  chEvtRegister(pktGetEventSource(&RPKTD1), &pkt_el, 1);
+  trace_enabled = true;
+}
+
+void pktDisableEventTrace() {
+  trace_enabled = false;
+  chEvtUnregister(pktGetEventSource(&RPKTD1), &pkt_el);
+}
+
+/*
+ * TODO: Refactor and add severity categories filtering
+ */
+void pktTraceEvents() {
+  if(!trace_enabled)
+    return;
+eventmask_t evt = chEvtGetAndClearEvents(EVENT_MASK(1));
+  if(evt) {
+    eventflags_t flags = chEvtGetAndClearFlags(&pkt_el);
+    if(flags & EVT_PWM_QUEUE_FULL) {
+      TRACE_WARN("PKT  > PWM queue full");
+    }
+    if(flags & EVT_PWM_FIFO_EMPTY) {
+      TRACE_WARN("PKT  > PWM FIFO exhausted");
+    }
+    if(flags & EVT_AX25_NO_BUFFER) {
+      TRACE_WARN("PKT  > AX25 FIFO exhausted");
+    }
+    if(flags & EVT_ICU_SLEEP_TIMEOUT) {
+      TRACE_INFO("PKT  > PWM ICU has entered sleep");
+    }
+    if(flags & EVT_AX25_BUFFER_FULL) {
+      TRACE_WARN("PKT  > AX25 receive buffer full");
+    }
+    if(flags & EVT_DECODER_ERROR) {
+      TRACE_ERROR("PKT  > Decoder error");
+    }
+    if(flags & EVT_PWM_UNKNOWN_INBAND) {
+      TRACE_ERROR("PKT  > Unknown PWM inband flag");
+    }
+    if(flags & EVT_ICU_OVERFLOW) {
+      TRACE_WARN("PKT  > PWM ICU overflow");
+    }
+    if(flags & EVT_PWM_STREAM_TIMEOUT) {
+      TRACE_WARN("PKT  > PWM steam timeout");
+    }
+    if(flags & EVT_PWM_NO_DATA) {
+      TRACE_WARN("PKT  > PWM data not started from radio");
+    }
+  }
+}

tracker/software/pkt/diagnostics/pktevt.h

@@ -0,0 +1,26 @@
+/*
+    Aerospace Decoder - Copyright (C) 2018 Bob Anderson (VK2GJ)
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+*/
+
+#ifndef PKT_DIAGNOSTICS_PKTEVT_H_
+#define PKT_DIAGNOSTICS_PKTEVT_H_
+
+/*===========================================================================*/
+/* External declarations.                                                    */
+/*===========================================================================*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+void pktTraceEvents(void);
+void pktEnableEventTrace(void);
+void pktDisableEventTrace(void);
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* PKT_DIAGNOSTICS_PKTEVT_H_ */

tracker/software/pkt/pktconf.h

@@ -157,8 +157,11 @@
 #include "ihex_out.h"
 #include "ax25_dump.h"
 #include "si446x.h"
+#include "pktevt.h"
 
-
+#ifndef PKT_IS_TEST_PROJECT
+#include "debug.h"
+#endif
 extern packet_svc_t RPKTD1;
 
 /*===========================================================================*/

tracker/software/pkt/protocols/txhdlc.c

@@ -23,6 +23,7 @@ void pktStreamIteratorInit(tx_iterator_t *iterator,
   uint16_t crc = calc_crc16(pp->frame_data, 0, pp->frame_len);
   iterator->crc[0] = crc & 0xFF;
   iterator->crc[1] = crc >> 8;
+  iterator->no_write = false;
   iterator->state = ITERATE_PREAMBLE;
 }
 
@@ -33,8 +34,8 @@ void pktStreamIteratorInit(tx_iterator_t *iterator,
  *
  */
 static bool pktIteratorWriteStream(tx_iterator_t *iterator, uint8_t bit) {
-  /* If new byte clear it first. */
+  /* If new output buffer byte clear it first if write is enabled. */
-  if(iterator->out_index % 8 == 0)
+  if((iterator->out_index % 8 == 0) && (iterator->no_write == false))
     iterator->out_buff[iterator->out_index >> 3] = 0;
 
   /* Normalize to bit 0. */
@@ -55,14 +56,18 @@ static bool pktIteratorWriteStream(tx_iterator_t *iterator, uint8_t bit) {
   iterator->nrzi_hist ^= (bit == 0) ? 0x1 : 0x0;
 
   /* Write NRZI bit to current byte. */
-  iterator->out_buff[iterator->out_index >> 3] |=
+  if(iterator->no_write == false)
-      (iterator->nrzi_hist & 0x1) << (iterator->out_index % 8);
+    iterator->out_buff[iterator->out_index >> 3] |=
+        (iterator->nrzi_hist & 0x1) << (iterator->out_index % 8);
 
-  /* If byte was completed and required quantity reached, return true. */
+  /* If byte was completed check quantity status. */
-  if((++iterator->out_index % 8) == 0)
+  if((iterator->inp_index % 8) == 0) {
-    return (++iterator->out_count == iterator->qty);
+    if((++iterator->out_count) == iterator->qty) {
-  else
+      //iterator->out_index = 0;
-    return false;
+      return true;
+    }
+  }
+  return false;
 }
 
 /*
@@ -70,10 +75,14 @@ static bool pktIteratorWriteStream(tx_iterator_t *iterator, uint8_t bit) {
  */
 static bool pktEncodeFrameHDLC(tx_iterator_t *iterator) {
   do {
+    iterator->inp_index++;
     if(pktIteratorWriteStream(iterator,
            ((iterator->hdlc_code >> iterator->hdlc_bit++) & 0x1)
-           << (iterator->out_index % 8)))
+           << (iterator->out_index % 8))) {
-        return true;
+      if(iterator->hdlc_bit == 8)
+        iterator->hdlc_bit = 0;
+      return true;
+    }
   } while(iterator->hdlc_bit < 8);
   iterator->hdlc_bit = 0;
   return false;
@@ -86,27 +95,21 @@ static bool pktEncodeFrameHDLC(tx_iterator_t *iterator) {
 static bool pktEncodeFrameData(tx_iterator_t *iterator) {
   do {
 
-    /*
-     * RLL encoding is enabled for the packet data pay load.
-     * Except the last data byte which is the HDLC flag.
-     */
-    if((iterator->hdlc_hist & HDLC_RLL_SEQUENCE) == HDLC_RLL_SEQUENCE) {
-      iterator->rll_count++;
-      /* Insert RLL 0 to HDLC output stream. */
-      if(pktIteratorWriteStream(iterator, 0)) {
-        //if(++iterator->out_count == iterator->qty)
-          return true;
-      }
-    }
     /* Get data bit. */
     uint8_t byte = iterator->data_buff[iterator->inp_index >> 3];
     uint8_t bit = (byte >> (iterator->inp_index % 8)) & 0x1;
 
     /* Indicate data input bit is consumed. Write to stream. */
     iterator->inp_index++;
-    if(pktIteratorWriteStream(iterator, bit)) {
+    if(pktIteratorWriteStream(iterator, bit))
-      //if(++iterator->out_count == iterator->qty)
       return true;
+
+    /* RLL encoding is enabled for the packet data pay load. */
+    if((iterator->hdlc_hist & HDLC_RLL_SEQUENCE) == HDLC_RLL_SEQUENCE) {
+      iterator->rll_count++;
+      /* Insert RLL 0 to output stream. */
+      if(pktIteratorWriteStream(iterator, 0))
+          return true;
     }
   } while((iterator->inp_index % 8) != 0);
   return false;
@@ -118,10 +121,13 @@ static bool pktEncodeFrameData(tx_iterator_t *iterator) {
  * @post    When the stream is complete the iterator may be re-used.
  * @notes   The iterator allows a frame to be encoded in chunks.
  * @notes   The calling function may request chunk sizes from 1 byte up.
+ * @notes   A quantity of 0 will return the number of bytes pending only.
+ * @notes   In this case no data is actually written to the stream.
  *
  * @param[in]   iterator   pointer to an @p iterator object.
  * @param[in]   stream     pointer to buffer to write stream data.
  * @param[in]   qty        the requested number of stream bytes.
+ *                         requesting 0 will return the stream bytes remaining.
  *
  * @return  number of bytes encoded.
  * @retval  zero indicates the iterator is not initialized or is finished.
@@ -131,22 +137,39 @@ static bool pktEncodeFrameData(tx_iterator_t *iterator) {
  * @api
  */
 uint16_t pktStreamEncodingIterator(tx_iterator_t *iterator,
-                                   uint8_t *stream, size_t qty) {
+                                   uint8_t *stream, uint16_t qty) {
 
-  if(qty == 0)
+  if(qty == 0) {
-    return 0;
+    tx_iterator_t saved;
 
+    /* Save state. */
+    saved = *iterator;
+    iterator->no_write = true;
+
+    /* Count the number of bytes remaining to output to the stream. */
+    uint16_t remain = pktStreamEncodingIterator(iterator, NULL, 0xFFFF);
+
+    /* Restore state. */
+    *iterator = saved;
+    return remain;
+  }
+
+  /* Each call has a new quantity and buffer which starts from index 0. */
   iterator->out_count = 0;
   iterator->qty = qty;
+  iterator->out_index = 0;
 
-  chDbgAssert(stream != NULL, "no stream buffer allocated");
+  chDbgAssert((stream != NULL) || (iterator->no_write == true),
+              "no stream buffer allocated");
 
   iterator->out_buff = stream;
 
   while(true) {
     switch(iterator->state) {
     case ITERATE_INIT:
-    case ITERATE_FINAL:
+      return 0;
+
+    case ITERATE_END:
       return 0;
 
     case ITERATE_PREAMBLE: {
@@ -160,7 +183,7 @@ uint16_t pktStreamEncodingIterator(tx_iterator_t *iterator,
           return iterator->qty;
       } /* End while. */
       iterator->state = ITERATE_FRAME;
-      break;
+      continue;
       } /* End case ITERATE_PREAMBLE. */
 
     case ITERATE_FRAME: {
@@ -173,12 +196,12 @@ uint16_t pktStreamEncodingIterator(tx_iterator_t *iterator,
           /* True means the requested count has been reached. */
           return iterator->qty;
       }
-      /* All frame data input consumed. */
+      /* All frame data input consumed. Switch to CRC fields. */
       iterator->state = ITERATE_CRC;
       iterator->data_buff = iterator->crc;
       iterator->data_size = sizeof(iterator->crc);
       iterator->inp_index = 0;
-      break;
+      continue;
       } /* End case ITERATE_FRAME. */
 
     case ITERATE_CRC: {
@@ -196,7 +219,8 @@ uint16_t pktStreamEncodingIterator(tx_iterator_t *iterator,
       iterator->hdlc_count = 10;
       iterator->hdlc_code = HDLC_FLAG;
       iterator->hdlc_bit = 0;
-      break;
+      iterator->inp_index = 0;
+      continue;
       } /* End case ITERATE_CRC. */
 
     case ITERATE_CLOSE: {
@@ -213,6 +237,7 @@ uint16_t pktStreamEncodingIterator(tx_iterator_t *iterator,
       /* Tail length. */
       iterator->hdlc_count = 10;
       iterator->hdlc_code = HDLC_ZERO;
+      continue;
       } /* End case ITERATE_CLOSE. */
 
     case ITERATE_TAIL: {
@@ -227,11 +252,17 @@ uint16_t pktStreamEncodingIterator(tx_iterator_t *iterator,
           return iterator->qty;
       } /* End while. */
       iterator->state = ITERATE_FINAL;
-      /* Round up to include any partial bits in next byte. */
+      continue;
-      if(iterator->out_index % 8 != 0)
-        ++iterator->out_count;
-      return (iterator->out_count);
       } /* End case ITERATE_TAIL. */
+
+    case ITERATE_FINAL: {
+      iterator->state = ITERATE_END;
+      /* Check for extra bits due to RLL. */
+      /* TODO: Calculate if RLL bits > 7 and feed out in QTY chunks. */
+      if((iterator->out_index % 8) != 0)
+        iterator->out_count++;
+      return iterator->out_count;
+      } /* End case ITERATE_FINAL. */
     } /* End switch on state. */
   } /* End while. */
 } /* End function. */

tracker/software/pkt/protocols/txhdlc.h

@@ -27,11 +27,13 @@ typedef enum {
   ITERATE_CRC,
   ITERATE_CLOSE,
   ITERATE_TAIL,
-  ITERATE_FINAL
+  ITERATE_FINAL,
+  ITERATE_END
 } txit_state_t;
 
 typedef struct {
   txit_state_t  state;
+  bool          no_write;
   uint16_t      qty;
   uint16_t      out_count;
   int16_t       hdlc_count;
@@ -58,7 +60,7 @@ typedef struct {
 extern "C" {
 #endif
   uint16_t pktStreamEncodingIterator(tx_iterator_t *iterator,
-                                     uint8_t *stream, size_t qty);
+                                     uint8_t *stream, uint16_t qty);
   void pktStreamIteratorInit(tx_iterator_t *iterator,
                              packet_t pp, bool scramble);
 #ifdef __cplusplus