Over the air testing is working

README.md

@@ -223,6 +223,19 @@ ADC performance is not critical, this pin can be connected to digital ground.
     # Used to send UDP packets.  The printf command supports non-printable.
     printf 'Hello\rWorld' | nc -u -w1 192.168.8.210 5198
 
+# Rig Integration Notes
+
+## Baofeng BF-F8HP HT
+
+* 3.5mm Jack
+  - Tip - NC
+  - Ring - Rig mic in, MicroLink audio out
+  - Sleeve - PTT when pulled to ground
+* 2.5mm Jack
+  - Tip - Rig speaker+ out, MicroLink audio in
+  - Ring - Rig ground
+  - Sleeve - Rig ground
+
 References
 ==========
 
@@ -246,11 +259,13 @@ References
   - [MCP4725 DAC](https://ww1.microchip.com/downloads/en/devicedoc/22039d.pdf)
   - [Audio Amp](https://www.ti.com/lit/ds/symlink/lm4862.pdf?HQS=dis-dk-null-digikeymode-dsf-pf-null-wwe&ts=1707335785542&ref_url=https%253A%252F%252Fwww.ti.com%252Fgeneral%252Fdocs%252Fsuppproductinfo.tsp%253FdistId%253D10%2526gotoUrl%253Dhttps%253A%252F%252Fwww.ti.com%252Flit%252Fgpn%252Flm4862)
   - [TLV9161 opamp suggested by Dan](https://www.ti.com/lit/ds/symlink/tlv9161.pdf?ts=1707743140015&ref_url=https%253A%252F%252Fwww.google.de%252F)
+  - [NTE3086 Optoisolator](https://www.nteinc.com/specs/3000to3099/pdf/nte3086.pdf)
 * Rig Integration
   - [Microphone Connector Reference](https://www.secradio.org.za/zs6src/secfiles/pdf/mic_soc_info.pdf)
   - [Baofeng Cable Reference](https://ics-ctrl.com/cable-pinout-baofeng-ht/)
 * Analog/Audio
   - [Good article from Analog Devices about noise in mixed-signal systems](https://www.analog.com/media/en/analog-dialogue/volume-46/number-2/articles/staying_well_grounded.pdf)
+  - [Detailed article about audio/rig integration](https://www.zs2ez.co.za/Soundcard/Soundcard.htm)
 * Other
   - [Analog Devices Filter Wizard](https://tools.analog.com/en/filterwizard/)
   - https://www.purevpn.com/what-is-vpn/protocols/openvpn

src/contexts/I2CAudioOutputContext.cpp

@@ -18,25 +18,36 @@
  * FOR AMATEUR RADIO USE ONLY.
  * NOT FOR COMMERCIAL USE WITHOUT PERMISSION.
  */
- #include <cmath>
+#include <cmath>
+
 #include "hardware/i2c.h"
 
+#include "common.h"
+#include "UserInfo.h"
 #include "I2CAudioOutputContext.h"
 
 namespace kc1fsz {
 
+// How long we wait in silence before deciding that the audio
+// output has stopped.
+static const uint32_t SQUELCH_INTERVAL_MS = 1000;
+
 I2CAudioOutputContext::I2CAudioOutputContext(uint32_t frameSize, uint32_t sampleRate,
-    uint32_t bufferDepthLog2, int16_t* audioBuf) 
+    uint32_t bufferDepthLog2, int16_t* audioBuf,
+    UserInfo* userInfo) 
 :   AudioOutputContext(frameSize, sampleRate),
     _bufferDepthLog2(bufferDepthLog2),
     _audioBuf(audioBuf),
+    _userInfo(userInfo),
     _frameWriteCount(0),
     _framePlayCount(0),
     _playPtr(0),
     _intervalUs(125),
     _idleCount(0),
     _overflowCount(0),
-    _playing(false)
+    _playing(false),
+    _squelchOpen(false),
+    _lastAudioTime(0)
 {
     _timer.setIntervalUs(_intervalUs);
     _dacAddr = 0x60;
@@ -66,8 +77,10 @@ void I2CAudioOutputContext::reset() {
     _inTone = false;
     _toneCount = 0;
     _toneStep = 0;
+    _squelchOpen = false;
+    _lastAudioTime = 0;
     _timer.reset();
-    // Park at middle of range
+    // Park DAC at middle of range
     _play(0);
 }
 
@@ -109,6 +122,7 @@ bool I2CAudioOutputContext::run() {
 
     if (activity) {
         if (_inTone) {
+
             // TODO: HAVE A GAIN SETTING
             _play((_toneBuf[_tonePtr >> 2]) >> 2);
             // Move across tone, looking for wrap
@@ -120,7 +134,7 @@ bool I2CAudioOutputContext::run() {
             _toneCount--;
             if (_toneCount == 0) {
                 _inTone = false;
-                // Park at middle of range
+                // Park DAC at middle of range
                 _play(0);
             }
         }
@@ -152,11 +166,19 @@ bool I2CAudioOutputContext::run() {
             } else {
                 _playing = false;
                 _idleCount++;
-                // Park at middle of range
+                // Park DAC at middle of range
                 _play(0);
             }
         }
     }
+
+    // Manage squelch off
+    if (_squelchOpen && 
+        (time_ms() - _lastAudioTime) > SQUELCH_INTERVAL_MS ) {
+        _squelchOpen = false;
+        _userInfo->setSquelchOpen(_squelchOpen);
+    }
+
     return activity;
 }
 
@@ -192,12 +214,27 @@ static void makeFrame1(uint8_t* buf, uint16_t data) {
     buf[1] = data & 0xff;
 }
 
+void I2CAudioOutputContext::_openSquelchIfNecessary() {
+    if (!_squelchOpen) {
+        _squelchOpen = true;
+        _userInfo->setSquelchOpen(_squelchOpen);
+    }
+}
+
 void I2CAudioOutputContext::_play(int16_t sample) {
+
+    if (sample != 0) {
+        _openSquelchIfNecessary();
+    }
+
     uint16_t centeredSample = (sample + 32767);
     uint8_t buf[3];
     makeFrame0(buf, centeredSample);
     // TODO: MAKE THIS NON-BLOCKING
     i2c_write_blocking(i2c_default, _dacAddr, buf, 3, true);
+
+    // Keep track of time for squelch purposes
+    _lastAudioTime = time_ms();
 }
 
 }

src/contexts/I2CAudioOutputContext.h

@@ -28,6 +28,8 @@
 
 namespace kc1fsz {
 
+class UserInfo;
+
 /**
  * An implementation of the AudioOutputContext that assumes a
  * MCP4725 DAC on an I2C interface using the Pi Pico SDK.
@@ -43,7 +45,8 @@ class I2CAudioOutputContext : public AudioOutputContext {
      * @param audioBuf Must be bufferDepth x frameSize in length.
     */
     I2CAudioOutputContext(uint32_t frameSize, uint32_t sampleRate, 
-        uint32_t bufferDepthLog2, int16_t* audioBuf);
+        uint32_t bufferDepthLog2, int16_t* audioBuf,
+        UserInfo* userInfo);
     virtual ~I2CAudioOutputContext();
 
     virtual void reset();
@@ -60,11 +63,13 @@ class I2CAudioOutputContext : public AudioOutputContext {
 private:
 
     void _play(int16_t pcm);
+    void _openSquelchIfNecessary();
 
     uint32_t _bufferDepthLog2;
     // How deep we should get before triggering the audio play
     uint32_t _triggerDepth;
     int16_t *_audioBuf;
+    UserInfo* _userInfo;
     uint32_t _frameWriteCount;
     uint32_t _framePlayCount;
     uint32_t _playPtr;
@@ -79,6 +84,11 @@ class I2CAudioOutputContext : public AudioOutputContext {
     // This indicates whether we are actually playing sound
     // vs. sitting in silence.
     bool _playing;
+    // Used to control squelch reporting
+    bool _squelchOpen;
+    // The last time we saw audio which can be used to 
+    // manage squelch.
+    uint32_t _lastAudioTime;
 
     // Tone features
     static const uint32_t _toneBufSize = 20;

src/contexts/PicoAudioInputContext.h

@@ -98,7 +98,7 @@ class PicoAudioInputContext : public Runnable {
     int16_t _dcBias = -95;
     // This includes x16 for 12 to 16 bit PCM conversion and a gain
     // of 0.5.
-    int16_t _gain = 15;
+    int16_t _gain = 16;
 
     bool _keyed = false;
 

src/machines/QSOFlowMachine.cpp

@@ -53,9 +53,6 @@ static const uint32_t RTCP_PORT = 5199;
 static const uint32_t KEEP_ALIVE_INTERVAL_MS = 10000;
 // How long we wait in silence before unkeying on TX
 static const uint32_t TX_TAIL_INTERVAL_MS = 1000;
-// How long we wait in silence before deciding that the remote
-// station has unkeyed.
-static const uint32_t SQUELCH_INTERVAL_MS = 1000;
 
 int QSOFlowMachine::traceLevel = 0;
 
@@ -77,7 +74,7 @@ void QSOFlowMachine::start() {
     _lastRxAudioTime = 0;
     _lastRxAudioSeq = 0;
     _audioSeqErrors = 0;
-    _squelchOpen = false;
+    //_squelchOpen = false;
     _stopRequested = false;
     _state = State::OPEN_RX;
     _gsmEncoder.reset();
@@ -105,10 +102,10 @@ void QSOFlowMachine::_processRXReceive(const UDPReceiveEvent* evt) {
 
             _lastRxAudioTime = time_ms();
 
-            if (!_squelchOpen) {
-                _squelchOpen = true;
-                _userInfo->setSquelchOpen(_squelchOpen);
-            }
+            //if (!_squelchOpen) {
+            //    _squelchOpen = true;
+            //    _userInfo->setSquelchOpen(_squelchOpen);
+            //}
 
             // Unload the GSM frames from the RTP packet
             uint16_t remoteSeq = 0;
@@ -260,10 +257,10 @@ void QSOFlowMachine::_processEvent(const Event* ev) {
     }
     else if (ev->getType() == TickEvent::TYPE) {
         // Timeout on squelch?
-        if (_squelchOpen && time_ms() - _lastRxAudioTime > SQUELCH_INTERVAL_MS) {
-            _squelchOpen = false;
-            _userInfo->setSquelchOpen(_squelchOpen);
-        }
+        //if (_squelchOpen && time_ms() - _lastRxAudioTime > SQUELCH_INTERVAL_MS) {
+        //    _squelchOpen = false;
+        //    _userInfo->setSquelchOpen(_squelchOpen);
+        //}
     }
 
     // Now deal with state-specific activity

src/machines/QSOFlowMachine.h

@@ -157,7 +157,7 @@ class QSOFlowMachine : public StateMachine {
     uint16_t _lastRxAudioSeq;
 
     // Indicates whether the system is actively receiving. 
-    bool _squelchOpen;
+    //bool _squelchOpen;
 
     // Buffer for outbound audio
     static const uint32_t _txAudioBufDepth = 2;

tests/TestUserInfo.h

@@ -5,6 +5,7 @@
 
 #include "kc1fsz-tools/AudioOutputContext.h"
 
+#include "../src/common.h"
 #include "../src/UserInfo.h"
 
 namespace kc1fsz {
@@ -20,24 +21,34 @@ class TestUserInfo : public UserInfo {
     virtual void setSquelchOpen(bool sq) { 
 
         bool unkey = _squelch == true && sq == false;
+
         _squelch = sq;
 
         std:: cout << "UserInfo: Squelch: " << _squelch << std::endl;
 
         // Short beep on unkey
+        //if (unkey) {
+        //    if (_audioOutCtx != 0) {
+        //        _audioOutCtx->tone(400, 75);
+        //    }
+        //}
+
         if (unkey) {
-            if (_audioOutCtx != 0) {
-                _audioOutCtx->tone(400, 75);
-            }
+            _lastSquelchCloseTime = time_ms();
         }
     }
 
     bool getSquelch() const { return _squelch; }
+
+    uint32_t getMsSinceLastSquelchClose() const { 
+        return time_ms() - _lastSquelchCloseTime; 
+    }
 
 private:
 
     bool _squelch = false;
     AudioOutputContext* _audioOutCtx = 0;
+    uint32_t _lastSquelchCloseTime = 0;
 };
 
 }