Merge branch 'AdvancedCVAck' into ESP32-IRAM_ATTR

* AdvancedCVAck:
  split out ServiceMode ackCV from Ops Mode AdvancedCVAck as doing a ackCV in Ops Mode is wrong and adds 6ms busy delay add cache of CV29 value
  bumped version to 2.0.2
  reverted changes around lastMicros
  added conditional compilation for ESP8266 to add ICACHE_RAM_ATTR to ExternalInterruptHandler changed storage for Micros to unsigned long
  changed the version to 201 in the header

# Conflicts:
#	NmraDcc.cpp
reverted to unsigned int

NmraDcc.cpp

@@ -93,7 +93,7 @@
 #define MAX_ONEBITHALF  82
 #define MIN_ONEBITFULL  82
 #define MIN_ONEBITHALF  35
-#define MAX_BITDIFF     18
+#define MAX_BITDIFF     24
 
 
 // Debug-Ports
@@ -217,18 +217,12 @@
     #define MODE_TP2 
     #define SET_TP2 
     #define CLR_TP2 
-        //#define MODE_TP2 DDRC |= (1<<2) // A2
-        //#define SET_TP2 PORTC |= (1<<2)
-        //#define CLR_TP2 PORTC &= ~(1<<2)
     #define MODE_TP3 
     #define SET_TP3 
     #define CLR_TP3 
     #define MODE_TP4 
     #define SET_TP4 
     #define CLR_TP4 
-        //#define MODE_TP4 DDRC |= (1<<4) //A4 
-        //#define SET_TP4 PORTC |= (1<<4) 
-        //#define CLR_TP4 PORTC &= ~(1<<4) 
     
 #endif
 #ifdef DEBUG_PRINT
@@ -343,9 +337,10 @@ void ExternalInterruptHandler(void)
 // Bit evaluation without Timer 0 ------------------------------
     uint8_t DccBitVal;
     static int8_t  bit1, bit2 ;
-    static word  lastMicros = 0;
+    static unsigned int  lastMicros = 0;
     static byte halfBit, DCC_IrqRunning;
     unsigned int  actMicros, bitMicros;
+    #ifdef ALLOW_NESTED_IRQ
     if ( DCC_IrqRunning ) {
         // nested DCC IRQ - obviously there are glitches
         // ignore this interrupt and increment glitchcounter
@@ -356,6 +351,7 @@ void ExternalInterruptHandler(void)
         SET_TP3;
         return; //>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> abort IRQ
     }
+    #endif
     SET_TP3;
     actMicros = micros();
     bitMicros = actMicros-lastMicros;
@@ -367,11 +363,12 @@ void ExternalInterruptHandler(void)
     }
     DccBitVal = ( bitMicros < bitMax );
     lastMicros = actMicros;
-    #ifdef debug
-    if(DccBitVal) {SET_TP2;} else {CLR_TP2;};
-    #endif
+    
+    #ifdef ALLOW_NESTED_IRQ
     DCC_IrqRunning = true;
     interrupts();  // time critical is only the micros() command,so allow nested irq's
+    #endif
+    
 #ifdef DCC_DEBUG
     DccProcState.TickCount++;
 #endif
@@ -432,13 +429,10 @@ void ExternalInterruptHandler(void)
             DccRx.BitCount++;
             if( abs(bit2-bit1) > MAX_BITDIFF ) {
                 // the length of the 2 halfbits differ too much -> wrong protokoll
-                CLR_TP2;
-                CLR_TP3;
                 DccRx.State = WAIT_PREAMBLE;
                 bitMax = MAX_PRAEAMBEL;
                 bitMin = MIN_ONEBITFULL;
                 DccRx.BitCount = 0;
-				SET_TP4;
 
         #if defined ( __STM32F1__ )
 				detachInterrupt( DccProcState.ExtIntNum );
@@ -565,6 +559,7 @@ void ExternalInterruptHandler(void)
     {
       CLR_TP3;
       DccRx.State = WAIT_PREAMBLE ;
+      DccRx.BitCount = 0 ;
       bitMax = MAX_PRAEAMBEL;
       bitMin = MIN_ONEBITFULL;
 #ifdef ESP32
@@ -594,9 +589,11 @@ void ExternalInterruptHandler(void)
         DccRx.TempByte = 0 ;
       }
   }
+  #ifdef ALLOW_NESTED_IRQ
+  DCC_IrqRunning = false;
+  #endif
   CLR_TP1;
   CLR_TP3;
-  DCC_IrqRunning = false;
 }
 
 void ackCV(void)
@@ -1362,6 +1359,17 @@ void NmraDcc::pin( uint8_t ExtIntNum, uint8_t ExtIntPinNum, uint8_t EnablePullup
 #if defined ( __STM32F1__ )
   // with STM32F1 the interuptnumber is equal the pin number
   DccProcState.ExtIntNum = ExtIntPinNum;
+  // because STM32F1 has a NVIC we must set interuptpriorities
+  const nvic_irq_num irqNum2nvic[] = { NVIC_EXTI0, NVIC_EXTI1, NVIC_EXTI2, NVIC_EXTI3, NVIC_EXTI4, 
+            NVIC_EXTI_9_5, NVIC_EXTI_9_5, NVIC_EXTI_9_5, NVIC_EXTI_9_5, NVIC_EXTI_9_5, 
+            NVIC_EXTI_15_10, NVIC_EXTI_15_10, NVIC_EXTI_15_10, NVIC_EXTI_15_10, NVIC_EXTI_15_10, NVIC_EXTI_15_10 };
+  exti_num irqNum =  (exti_num)(PIN_MAP[ExtIntPinNum].gpio_bit); 
+
+// DCC-Input IRQ must be able to interrupt other long low priority ( level15 ) IRQ's  
+  nvic_irq_set_priority ( irqNum2nvic[irqNum], PRIO_DCC_IRQ); 
+  
+// Systic must be able to interrupt DCC-IRQ to always get correct micros() values  
+  nvic_irq_set_priority(NVIC_SYSTICK, PRIO_SYSTIC); 
 #else
   DccProcState.ExtIntNum = ExtIntNum;
 #endif

NmraDcc.h

@@ -53,6 +53,8 @@
 
 #define MAX_DCC_MESSAGE_LEN 6    // including XOR-Byte
 
+//#define ALLOW_NESTED_IRQ      // uncomment to enable nested IRQ's ( only for AVR! )
+
 typedef struct
 {
 	uint8_t	Size ;
@@ -105,6 +107,9 @@ typedef struct
 #elif defined( __STM32F1__)
 	#define MAXCV	(EEPROM_PAGE_SIZE/4 - 1)	// number of storage places (CV address could be larger
 											// because STM32 uses virtual adresses)
+    #undef ALLOW_NESTED_IRQ                 // This is done with NVIC on STM32
+    #define PRIO_DCC_IRQ    9
+    #define PRIO_SYSTIC     8               // MUST be higher priority than DCC Irq
 #else
 	#define MAXCV    E2END     					// the upper limit of the CV value currently defined to max memory.
 #endif