Added function to radio API allowing to fine tune the radio's VCXO polarisation voltage. Currently, this functionality is effective only on MD-3x0 devices. (TG-195 #ready-for-test)

openrtx/include/input.h

@@ -23,14 +23,16 @@
 #include <inttypes.h>
 #include <stdbool.h>
 
-/* This function returns true if at least one number is pressed on the
+/**
+ * This function returns true if at least one number is pressed on the
  * keyboard.
  * @param msg: the keyboard queue message
  * @return true if at least a number is pressed on the keyboard
  */
 bool input_isNumberPressed(kbd_msg_t msg);
 
-/* This function returns the smallest number that is pressed on the keyboard,
+/**
+ * This function returns the smallest number that is pressed on the keyboard,
  * 0 if none is pressed.
  * @param msg: the keyboard queue message
  * @return the smalled pressed number on the keyboard

openrtx/include/interfaces/radio.h

@@ -55,6 +55,19 @@ void radio_init(const rtxStatus_t *rtxState);
  */
 void radio_terminate();
 
+/**
+ * This function allows to fine tune the VCXO frequency by acting on the
+ * polarisation voltage.
+ * The offset parameters allowed range of ±32768 and they are algebraically
+ * added to the tuning value provided by the manufacturer's calibration data.
+ * Not calling this function results in leaving the VCXO tuning as provided by
+ * the manufacturer's calibration data.
+ *
+ * @param vhfOffset: VCXO tuning offset for VHF band.
+ * @param uhfOffset: VCXO tuning offset for UHF band.
+ */
+void radio_tuneVcxo(const int16_t vhfOffset, const int16_t uhfOffset);
+
 /**
  * Set current operating mode.
  *

platform/drivers/baseband/radio_GDx.cpp

@@ -96,6 +96,14 @@ void radio_terminate()
     SIM->SCGC6 &= ~SIM_SCGC6_DAC0_MASK;
 }
 
+void radio_tuneVcxo(const int16_t vhfOffset, const int16_t uhfOffset)
+{
+    //TODO: this part will be implemented in the future, when proved to be
+    // necessary.
+    (void) vhfOffset;
+    (void) uhfOffset;
+}
+
 void radio_setOpmode(const enum opmode mode)
 {
     switch(mode)

platform/drivers/baseband/radio_MD3x0.cpp

@@ -160,6 +160,29 @@ void radio_terminate()
     RCC->APB1ENR &= ~RCC_APB1ENR_DACEN;
 }
 
+void radio_tuneVcxo(const int16_t vhfOffset, const int16_t uhfOffset)
+{
+    (void) vhfOffset;
+
+    /*
+     * Adjust VCXO bias voltage acting on the value stored in MCU's DAC.
+     * Data from calibration is first converted to int16_t, then the value for
+     * the DAC register is computed according to which is done inside TYT's
+     * firmware.
+     * The signed offset is then added to this value, the result is constrained
+     * in the range [0 4095], converted to uint16_t and written into the DAC
+     * register.
+     *
+     * NOTE: we deliberately chose not to update the HR_C5000 modulation offset
+     * register, as we still have to deeply understand how TYT computes
+     * the values written there.
+     */
+    int16_t calValue  = static_cast< int16_t >(calData->freqAdjustMid);
+    int16_t oscTune   = (calValue*4 + 0x600) + uhfOffset;
+    oscTune           = std::max(std::min(oscTune, int16_t(4095)), int16_t(0));
+    DAC->DHR12R2      = static_cast< uint16_t >(oscTune);
+}
+
 void radio_setOpmode(const enum opmode mode)
 {
     switch(mode)

platform/drivers/baseband/radio_MD9600.cpp

@@ -30,6 +30,12 @@ void radio_terminate()
 
 }
 
+void radio_tuneVcxo(const int16_t vhfOffset, const int16_t uhfOffset)
+{
+    (void) vhfOffset;
+    (void) uhfOffset;
+}
+
 void radio_setOpmode(const enum opmode mode)
 {
     (void) mode;
@@ -37,7 +43,7 @@ void radio_setOpmode(const enum opmode mode)
 
 bool radio_checkRxDigitalSquelch()
 {
-    return true;
+    return false;
 }
 
 void radio_enableRx()

platform/drivers/baseband/radio_UV3x0.cpp

@@ -100,6 +100,14 @@ void radio_terminate()
     RCC->APB1ENR &= ~RCC_APB1ENR_DACEN;
 }
 
+void radio_tuneVcxo(const int16_t vhfOffset, const int16_t uhfOffset)
+{
+    //TODO: this part will be implemented in the future, when proved to be
+    // necessary.
+    (void) vhfOffset;
+    (void) uhfOffset;
+}
+
 void radio_setOpmode(const enum opmode mode)
 {
     switch(mode)

platform/drivers/baseband/radio_linux.cpp

@@ -33,6 +33,13 @@ void radio_terminate()
     puts("radio_linux: terminate() called");
 }
 
+void radio_tuneVcxo(const int16_t vhfOffset, const int16_t uhfOffset)
+{
+    (void) vhfOffset;
+    (void) uhfOffset;
+    puts("radio_linux: tuneVcxo() called");
+}
+
 void radio_setOpmode(const enum opmode mode)
 {
     std::string mStr(" ");