Slow down display of BW and SNR

Add a timer for display.

TEF6686_ESP32.ino

@@ -141,6 +141,8 @@ uint16_t SWMIBandPosold;  // Fix Me: Should store this parameter into flash, for
 String SWMIBandstring = String();
 String SWMIBandstringold = String();
 int lowsignaltimer;
+int bwupdatetimer;
+int snrupdatetimer;
 int menuoption = 30;
 int MStatusold;
 int OStatusold;
@@ -2809,6 +2811,9 @@ void ShowSignalLevel() {
   if (screenmute == false) {
     if (band == BAND_FM) SNR = int(0.46222375 * (float)(SStatus / 10) - 0.082495118 * (float)(USN / 10)) + 10; else SNR = -((int8_t)(USN / 10));
 
+    if (millis() >= snrupdatetimer + TIMER_500_TICK) {
+      snrupdatetimer = millis();
+
       if (SNR > (SNRold + 1) || SNR < (SNRold - 1)) {
         tft.setFreeFont(FONT7);
         tft.setTextColor(TFT_BLACK);
@@ -2822,6 +2827,7 @@ void ShowSignalLevel() {
           SNRold = 99;
         }
       }
+    }
 
     SAvg = (((SAvg * 9) + 5) / 10) + SStatus;
     SAvg2 = (((SAvg2 * 9) + 5) / 10) + SNR;
@@ -3134,6 +3140,9 @@ void doSquelch() {
 }
 
 void updateBW() {
+  if (millis() >= bwupdatetimer + TIMER_500_TICK) {
+    bwupdatetimer = millis();
+
     tft.setFreeFont(FONT7);
     if (BWset == 0) {
       if (screenmute == false) {
@@ -3148,6 +3157,7 @@ void updateBW() {
       }
     }
     tft.drawCentreString("AUTO BW", 282, 33, GFXFF);
+  }
 }
 
 void updateiMS() {

src/TEF6686.h

@@ -19,6 +19,10 @@ enum RADIO_TUNE_MODE {
   TUNE_MAN, TUNE_AUTO, TUNE_MEM, TUNE_MI_BAND
 };
 
+#define TIMER_BW_TIMER             (TIMER_500_TICK)
+#define TIMER_SNR_TIMER            (TIMER_500_TICK)
+#define TIMER_500_TICK             500
+
 #define BAT_LEVEL_EMPTY            1600
 #define BAT_LEVEL_WARN             1700
 #define BAT_LEVEL_FULL             2270