Implemented RX tone squelch on MD-UV3x0 and GDx (TG-43)

openrtx/include/rtx/OpMode_FM.h

@@ -83,7 +83,8 @@ public:
 
 private:
 
-    bool sqlOpen;   ///< Flag for current squelch status.
+    bool rfSqlOpen; ///< Flag for RF squelch status (analog squelch).
+    bool sqlOpen;   ///< Flag for squelch status.
     bool enterRx;   ///< Flag for RX management.
 };
 

openrtx/src/rtx/OpMode_FM.cpp

@@ -66,7 +66,7 @@ void _setVolume()
 }
 #endif
 
-OpMode_FM::OpMode_FM() : sqlOpen(false), enterRx(true)
+OpMode_FM::OpMode_FM() : rfSqlOpen(false), sqlOpen(false), enterRx(true)
 {
 }
 
@@ -77,8 +77,9 @@ OpMode_FM::~OpMode_FM()
 void OpMode_FM::enable()
 {
     // When starting, close squelch and prepare for entering in RX mode.
-    sqlOpen = false;
+    rfSqlOpen = false;
-    enterRx = true;
+    sqlOpen   = false;
+    enterRx   = true;
 }
 
 void OpMode_FM::disable()
@@ -87,8 +88,9 @@ void OpMode_FM::disable()
     audio_disableAmp();
     audio_disableMic();
     radio_disableRtx();
-    sqlOpen = false;
+    rfSqlOpen = false;
-    enterRx = false;
+    sqlOpen   = false;
+    enterRx   = false;
 }
 
 void OpMode_FM::update(rtxStatus_t *const status, const bool newCfg)
@@ -98,28 +100,34 @@ void OpMode_FM::update(rtxStatus_t *const status, const bool newCfg)
     // RX logic
     if(status->opStatus == RX)
     {
+        // RF squelch mechanism
         float squelch = -127.0f + status->sqlLevel * 66.0f / 15.0f;
         float rssi    = rtx_getRssi();
+        if((rfSqlOpen == false) && (rssi > (squelch + 0.1f))) rfSqlOpen = true;
+        if((rfSqlOpen == true)  && (rssi < (squelch - 0.1f))) rfSqlOpen = false;
 
-        if((sqlOpen == false) && (rssi > (squelch + 0.1f)))
+        // Local flags for current RF and tone squelch status
+        bool rfSql   = ((status->rxToneEn == 0) && (rfSqlOpen == true));
+        bool toneSql = ((status->rxToneEn == 1) && radio_checkRxDigitalSquelch());
+
+        // Audio control
+        if((sqlOpen == false) && (rfSql || toneSql))
         {
             audio_enableAmp();
             sqlOpen = true;
         }
 
-        if((sqlOpen == true) && (rssi < (squelch - 0.1f)))
+        if((sqlOpen == true) && (rfSql == false) && (toneSql == false))
         {
             audio_disableAmp();
             sqlOpen = false;
         }
 
         #ifdef PLATFORM_MDUV3x0
-        if(sqlOpen == true)
+        // Set output volume by changing the HR_C6000 DAC gain
-        {
+        if(sqlOpen == true) _setVolume();
-            // Set output volume by changing the HR_C6000 DAC gain
-            _setVolume();
-        }
         #endif
+
     }
     else if((status->opStatus == OFF) && enterRx)
     {
@@ -130,7 +138,7 @@ void OpMode_FM::update(rtxStatus_t *const status, const bool newCfg)
         enterRx = false;
     }
 
-    /* TX logic */
+    // TX logic
     if(platform_getPttStatus() && (status->opStatus != TX) &&
                                   (status->txDisable == 0))
     {
@@ -156,13 +164,20 @@ void OpMode_FM::update(rtxStatus_t *const status, const bool newCfg)
     switch(status->opStatus)
     {
         case RX:
-            if(sqlOpen)
+            if(radio_checkRxDigitalSquelch())
             {
-                platform_ledOn(GREEN);
+                platform_ledOn(GREEN);  // Red + green LEDs ("orange"): tone squelch open
+                platform_ledOn(RED);
+            }
+            else if(rfSqlOpen)
+            {
+                platform_ledOn(GREEN);  // Green LED only: RF squelch open
+                platform_ledOff(RED);
             }
             else
             {
                 platform_ledOff(GREEN);
+                platform_ledOff(RED);
             }
 
             break;

platform/drivers/baseband/AT1846S.h

@@ -96,6 +96,7 @@ public:
 
     /**
      * Set the VCO frequency, either for transmission or reception.
+     *
      * @param freq: VCO frequency.
      */
     void setFrequency(const freq_t freq)
@@ -113,18 +114,21 @@ public:
 
     /**
      * Set the transmission and reception bandwidth.
+     *
      * @param band: bandwidth.
      */
     void setBandwidth(const AT1846S_BW band);
 
     /**
      * Set the operating mode.
+     *
      * @param mode: operating mode.
      */
     void setOpMode(const AT1846S_OpMode mode);
 
     /**
      * Set the functional mode.
+     *
      * @param mode: functional mode.
      */
     void setFuncMode(const AT1846S_FuncMode mode)
@@ -140,14 +144,42 @@ public:
 
     /**
      * Enable the CTCSS tone for transmission.
+     *
      * @param freq: CTCSS tone frequency.
      */
     void enableTxCtcss(const tone_t freq)
     {
-        i2c_writeReg16(0x4A, freq*10);
+        i2c_writeReg16(0x4A, freq*10);          // Set CTCSS1 frequency reg.
-        i2c_writeReg16(0x4B, 0x0000);
+        i2c_writeReg16(0x4B, 0x0000);           // Clear CDCSS bits
         i2c_writeReg16(0x4C, 0x0000);
-        maskSetRegister(0x4E, 0x0600, 0x0600);
+        maskSetRegister(0x4E, 0x0600, 0x0600);  // Enable CTCSS TX
+    }
+
+    /**
+     * Enable the CTCSS tone detection during reception.
+     *
+     * @param freq: CTCSS tone frequency.
+     */
+    void enableRxCtcss(const tone_t freq)
+    {
+        i2c_writeReg16(0x4D, freq*10);          // Set CTCSS2 frequency reg.
+        i2c_writeReg16(0x5B, getCtcssThreshFromTone(freq));
+        maskSetRegister(0x3A, 0x001F, 0x0008);  // Enable CTCSS2 freq. detection
+    }
+
+    /**
+     * Check if CTCSS tone is detected when in RX mode.
+     *
+     * @return true if the RX CTCSS tone is being detected.
+     */
+    inline bool rxCtcssDetected()
+    {
+        // Check if CTCSS detection is enabled: if not, return false.
+        if((i2c_readReg16(0x3A) & 0x0008) == 0) return false;
+
+        // Check CTCSS2 compare flag
+        uint16_t reg  = i2c_readReg16(0x1C);
+        return ((reg & 0x100) != 0);
     }
 
     /**
@@ -155,12 +187,15 @@ public:
      */
     inline void disableCtcss()
     {
-        i2c_writeReg16(0x4A, 0x0000);
+        maskSetRegister(0x4E, 0x0600, 0x0000);  // Disable TX CTCSS
-        maskSetRegister(0x4E, 0x0600, 0x0000); // Disable TX CTCSS
+        maskSetRegister(0x3A, 0x001F, 0x0000);  // Disable CTCSS freq. detection
+        i2c_writeReg16(0x4A, 0x0000);           // Clear CTCSS1 frequency reg.
+        i2c_writeReg16(0x4D, 0x0000);           // Clear CTCSS2 frequency reg.
     }
 
     /**
      * Get current RSSI value.
+     *
      * @return current RSSI in dBm.
      */
     inline int16_t readRSSI()
@@ -171,6 +206,7 @@ public:
 
     /**
      * Set the gain of internal programmable gain amplifier.
+     *
      * @param gain: PGA gain.
      */
     inline void setPgaGain(const uint8_t gain)
@@ -181,6 +217,7 @@ public:
 
     /**
      * Set microphone gain for transmission.
+     *
      * @param gain: microphone gain.
      */
     inline void setMicGain(const uint8_t gain)
@@ -190,6 +227,7 @@ public:
 
     /**
      * Set maximum FM transmission deviation.
+     *
      * @param dev: maximum allowed deviation.
      */
     inline void setTxDeviation(const uint16_t dev)
@@ -200,6 +238,7 @@ public:
 
     /**
      * Set the gain for internal automatic gain control system.
+     *
      * @param gain: AGC gain.
      */
     inline void setAgcGain(const uint8_t gain)
@@ -210,6 +249,7 @@ public:
 
     /**
      * Set audio gain for recepion.
+     *
      * @param analogDacGain: "analog DAC gain" in AT1846S manual.
      * @param digitalGain: "digital voice gain" in AT1846S manual.
      */
@@ -223,6 +263,7 @@ public:
 
     /**
      * Set noise1 thresholds for squelch opening and closing.
+     *
      * @param highTsh: upper threshold.
      * @param lowTsh: lower threshold.
      */
@@ -234,6 +275,7 @@ public:
 
     /**
      * Set noise2 thresholds for squelch opening and closing.
+     *
      * @param highTsh: upper threshold.
      * @param lowTsh: lower threshold.
      */
@@ -245,6 +287,7 @@ public:
 
     /**
      * Set RSSI thresholds for squelch opening and closing.
+     *
      * @param highTsh: upper threshold.
      * @param lowTsh: lower threshold.
      */
@@ -256,6 +299,7 @@ public:
 
     /**
      * Set PA drive control bits.
+     *
      * @param value: PA drive value.
      */
     inline void setPaDrive(const uint8_t value)
@@ -266,6 +310,7 @@ public:
 
     /**
      * Set threshold for analog FM squelch opening.
+     *
      * @param thresh: squelch threshold.
      */
     inline void setAnalogSqlThresh(const uint8_t thresh)
@@ -332,6 +377,67 @@ private:
      * @param reg: address of the register to be read.
      */
     uint16_t i2c_readReg16(const uint8_t reg);
+
+    /**
+     * This function returns the value to be written into the AT1846S CTCSS
+     * threshold register when enabling the detection in RX mode.
+     * Values were obtained from the function contained in TYT firmware for
+     * MD-UV380 version S18.16 at address 0x0806ba2c.
+     *
+     * @param tone: tone_t variable specifying the CTCSS tone.
+     * @return an uint16_t value to be written directly into AT1846S
+     *         CTCSS threshold register.
+     */
+    uint16_t getCtcssThreshFromTone(const tone_t tone)
+    {
+        switch(tone)
+        {
+            case 670:  return 0x0C0D; break;    // 67.0 Hz
+            case 693:  return 0x0C0C; break;    // 69.3 Hz
+            case 719:  return 0x0B0B; break;    // 71.9 Hz
+            case 744:                           // 74.4 Hz
+            case 770:  return 0x0A0A; break;    // 77.0 Hz
+            case 797:                           // 79.7 Hz
+            case 825:  return 0x0909; break;    // 82.5 Hz
+            case 854:                           // 85.4 Hz
+            case 885:  return 0x0808; break;    // 88.5 Hz
+            case 915:                           // 91.5 Hz
+            case 948:  return 0x0707; break;    // 94.8 Hz
+            case 974:  return 0x0706; break;    // 97.4 Hz
+            case 1000:                          // 100.0Hz
+            case 1034: return 0x0606; break;    // 103.4Hz
+            case 1072:                          // 107.2Hz
+            case 1109: return 0x0605; break;    // 110.9Hz
+            case 1148: return 0x0505; break;    // 114.8Hz
+            case 1188:                          // 118.8Hz
+            case 1230: return 0x0504; break;    // 123.0Hz
+            case 1273:                          // 127.3Hz
+            case 1318: return 0x0404; break;    // 131.8Hz
+            case 1365:                          // 136.5Hz
+            case 1413:                          // 141.3Hz
+            case 1462: return 0x0403; break;    // 146.2Hz
+            case 1514: return 0x0504; break;    // 151.4Hz
+            case 1567:                          // 156.7Hz
+            case 1622:                          // 162.2Hz
+            case 1679:                          // 167.9Hz
+            case 1713:                          // 171.3Hz
+            case 1799: return 0x0403; break;    // 179.9Hz
+            case 1862: return 0x0400; break;    // 186.2Hz
+            case 1928: return 0x0302; break;    // 192.8Hz
+            case 2035:                          // 203.5Hz
+            case 2107:                          // 210.7Hz
+            case 2181:                          // 218.1Hz
+            case 2257: return 0x0302; break;    // 225.7Hz
+            case 2336:                          // 233.6Hz
+            case 2418:                          // 241.8Hz
+            case 2503: return 0x0300; break;    // 250.3Hz
+
+                                                // 159.8Hz, 165.5Hz, 173.8Hz,
+                                                // 177.3Hz, 183.5Hz, 189.9Hz,
+                                                // 196.6Hz, 199.5Hz, 206.5Hz,
+            default:   return 0x0505; break;    // 229.1Hz, 254.1Hz
+        }
+    }
 };
 
 #endif /* AT1846S_H */

platform/drivers/baseband/radio_GDx.cpp

@@ -119,7 +119,7 @@ void radio_setOpmode(const enum opmode mode)
 
 bool radio_checkRxDigitalSquelch()
 {
-    return true;
+    return at1846s.rxCtcssDetected();
 }
 
 void radio_enableRx()
@@ -152,6 +152,11 @@ void radio_enableRx()
     }
 
     radioStatus = RX;
+
+    if(config->rxToneEn)
+    {
+        at1846s.enableRxCtcss(config->rxTone);
+    }
 }
 
 void radio_enableTx()
@@ -204,11 +209,12 @@ void radio_disableRtx()
 
     if(radioStatus == TX)
     {
-        at1846s.disableCtcss();
+        // Set PA drive voltage to 0V
         DAC0->DAT[0].DATH = 0;
         DAC0->DAT[0].DATL = 0;
     }
 
+    at1846s.disableCtcss();
     at1846s.setFuncMode(AT1846S_FuncMode::OFF);
     radioStatus = OFF;
 }

platform/drivers/baseband/radio_MD3x0.cpp

@@ -191,7 +191,7 @@ void radio_setOpmode(const enum opmode mode)
 
 bool radio_checkRxDigitalSquelch()
 {
-    return true;
+    return false;
 }
 
 void radio_enableRx()

platform/drivers/baseband/radio_UV3x0.cpp

@@ -125,7 +125,7 @@ void radio_setOpmode(const enum opmode mode)
 
 bool radio_checkRxDigitalSquelch()
 {
-    return true;
+    return at1846s.rxCtcssDetected();
 }
 
 void radio_enableRx()
@@ -151,6 +151,11 @@ void radio_enableRx()
         gpio_setPin(UHF_LNA_EN);
     }
 
+    if(config->rxToneEn)
+    {
+        at1846s.enableRxCtcss(config->rxTone);
+    }
+
     radioStatus = RX;
 }
 
@@ -225,10 +230,10 @@ void radio_disableRtx()
     // If we are currently transmitting, stop tone and C6000 TX
     if(radioStatus == TX)
     {
-        at1846s.disableCtcss();
         C6000.stopAnalogTx();
     }
 
+    at1846s.disableCtcss();
     at1846s.setFuncMode(AT1846S_FuncMode::OFF);
     radioStatus = OFF;
 }