Tidy ups, readme, comments

README.md

@@ -31,6 +31,7 @@ ENABLE_COMPANDER              := 1       compander option (per channel)
 ENABLE_SHOW_CHARGE_LEVEL      := 1       show the charge level when the radio is on charge 
 ENABLE_REVERSE_BAT_SYMBOL     := 1       mirror the battery symbol on the status bar (+ pole on the right)
 ENABLE_AM_FIX                 := 1       dynamically adjust the front end gains when in AM mode to helo prevent AM demodulator saturation - ignore the on-screen RSSI (for now)
+ENABLE_SQUELCH1_LOWER         := 1       adjusts squelch setting '1' to be more sensitive - I plan to let user adjust it in the menu
 ENABLE_AUDIO_BAR              := 0       experimental, display an audo bar level when TX'ing
 #ENABLE_SINGLE_VFO_CHAN       := 1       not yet implemented - single VFO on display when possible
 #ENABLE_BAND_SCOPE            := 1       not yet implemented - spectrum/pan-adapter

app/app.c

@@ -84,14 +84,14 @@ const uint16_t  orig_pga       = 6;   //  -3dB
 		uint16_t     sum;           // sum of all samples in the buffer
 	} moving_avg_rssi;
 
-	unsigned int am_fix_increase_counter = 0;
+	unsigned int am_gain_hold_counter = 0;
 
 	void APP_reset_AM_fix(void)
 	{
 		// reset the moving average filter
 		memset(&moving_avg_rssi, 0, sizeof(moving_avg_rssi));
 
-		am_fix_increase_counter = 0;
+		am_gain_hold_counter = 0;
 	}
 
 #endif
@@ -1403,27 +1403,27 @@ void APP_CheckKeys(void)
 		// -87dBm, any higher and the AM demodulator starts to saturate/clip (distort)
 		const uint16_t desired_rssi = (-87 + 160) * 2;   // dBm to ADC sample
 
-		// start with current settings
+		// start with the current gain settings
 		register uint16_t new_lna_short = am_lna_short;
 		register uint16_t new_lna       = am_lna;
 		register uint16_t new_mixer     = am_mixer;
 		register uint16_t new_pga       = am_pga;
 
+		// current RX frequency
+		const uint32_t rx_frequency = gRxVfo->pRX->Frequency;
+
 		// max gains to use
-//		uint16_t max_lna_short = orig_lna_short;
+//		uint16_t max_lna_short = orig_lna_short;     // we're not altering this one
 		uint16_t max_lna       = orig_lna;
 		uint16_t max_mixer     = orig_mixer;
 		uint16_t max_pga       = orig_pga;
 
-		const uint32_t rx_frequency = gRxVfo->pRX->Frequency;
-
-		// the RX gain abrutly reduces above this frequency
-		if (rx_frequency <= 22640000)
+		if (rx_frequency <= 22640000)         // the RX gain abrutly reduces above this frequency
 		{
 			max_pga = 7;
 		}
 		else
-		{
+		{	// allow a bit more gain
 //			max_lna = 4;
 			max_lna = 7;
 			max_pga = 7;
@@ -1443,7 +1443,8 @@ void APP_CheckKeys(void)
 			moving_avg_rssi.index = 0;                                          // wrap-a-round
 		rssi = moving_avg_rssi.sum / moving_avg_rssi.count;                     // compute the average of the past 'n' samples
 
-		// the register adjustments below to be more inteligent in order to maintain a good stable setting
+		// the register adjustments below need to be more intelligent
+		// in order to maintain a good stable setting
 
 		if (rssi > desired_rssi)
 		{	// decrease gain
@@ -1469,39 +1470,40 @@ void APP_CheckKeys(void)
 //			if (new_lna_short > 0)
 //				new_lna_short--;
 
-			am_fix_increase_counter = 50;           // 500ms
+			am_gain_hold_counter = 50;           // 500ms
 		}
 
-		if (am_fix_increase_counter > 0)
-			am_fix_increase_counter--;
+		if (am_gain_hold_counter > 0)
+			am_gain_hold_counter--;
 
-		if (am_fix_increase_counter == 0)
+		if (am_gain_hold_counter == 0)
+		{	// hold has been released, we're now free to increase gain
+
+			if (rssi < (desired_rssi - 10))      // 5dB hysterisis - to help prevent gain hunting
 			{	// increase gain
 
-			if (rssi < (desired_rssi - 10))
-			{	// increase gain
 				if (new_pga < max_pga)
 				{
 					new_pga++;
-					am_fix_increase_counter = 10;   // 100ms
+					am_gain_hold_counter = 10;   // 100ms
 				}
 				else
 				if (new_mixer < max_mixer)
 				{
 					new_mixer++;
-					am_fix_increase_counter = 10;   // 100ms
+					am_gain_hold_counter = 10;   // 100ms
 				}
 				else
 				if (new_lna < max_lna)
 				{
 					new_lna++;
-					am_fix_increase_counter = 10;   // 100ms
+					am_gain_hold_counter = 10;   // 100ms
 				}
 //				else
 //				if (new_lna_short < max_lna_short)
 //				{
 //					new_lna_short++;
-//					am_fix_increase_counter = 10;   // 100ms
+//					am_gain_hold_counter = 10;   // 100ms
 //				}
 			}
 		}
@@ -1511,6 +1513,7 @@ void APP_CheckKeys(void)
 
 		// apply the new gain settings to the front end
 
+		// remember the new gain settings - for the next time this function is called
 		am_lna_short = new_lna_short;
 		am_lna       = new_lna;
 		am_mixer     = new_mixer;
@@ -1519,7 +1522,6 @@ void APP_CheckKeys(void)
 		BK4819_WriteRegister(BK4819_REG_13, (am_lna_short << 8) | (am_lna << 5) | (am_mixer << 3) | (am_pga << 0));
 
 
-
 		// TODO: offset the RSSI reading to the rest of the firmware to cancel out the gain adjustments we've made here
 
 

version.c

@@ -2,7 +2,7 @@
 #ifdef GIT_HASH
 	#define VER     GIT_HASH
 #else
-	#define VER     "230922"
+	#define VER     "230923"
 #endif
 
 const char Version[]      = "OEFW-"VER;