RS485 Data Dropping

examples/RS485Deferred/RS485Deferred.ino

@@ -0,0 +1,73 @@
+/*
+  The purpose of this example is to demonstrate how the Arudino Mega will drop incoming RS485 data if
+  processing is done in the ISR.
+
+  #define DCSBIOS_DEFER_RS485_PROCESSING is enabled in this sketch, comment
+  it out to see the problem. You don't need all LED's to be physicallyconnected, just any one that is
+  supposed to be blinking.
+
+  Even though the sketch uses efficient direct register access, this sketch will still drop data and
+  not blink the LEDs in sync with the sim unless DCSBIOS_DEFER_RS485_PROCESSING is defined.
+*/
+
+#define DCSBIOS_RS485_SLAVE 23 // The following #define tells DCS-BIOS that this is a RS-485 slave device. It also sets the address of this slave device. The slave address should be between 1 and 126 and must be unique among all devices on the same bus.
+#define TXENABLE_PIN 2 // The Arduino pin that is connected to the /RE and DE pins on the RS-485 transceiver.
+#define DCSBIOS_DEFER_RS485_PROCESSING // Defer RS485 processing from the ISR to loop().
+#include "DcsBios.h"
+
+void onClA1Change(unsigned int newValue) { if (newValue == 1) { PORTE |= (1 << 5); } else { PORTE &= ~(1 << 5); } } DcsBios::IntegerBuffer clA1Buffer(0x10d4, 0x0001, 0, onClA1Change);
+void onClA2Change(unsigned int newValue) { if (newValue == 1) { PORTG |= (1 << 5); } else { PORTG &= ~(1 << 5); } } DcsBios::IntegerBuffer clA2Buffer(0x10d4, 0x0002, 1, onClA2Change);
+void onClA3Change(unsigned int newValue) { if (newValue == 1) { PORTE |= (1 << 3); } else { PORTE &= ~(1 << 3); } } DcsBios::IntegerBuffer clA3Buffer(0x10d4, 0x0004, 2, onClA3Change);
+void onClA4Change(unsigned int newValue) { if (newValue == 1) { PORTH |= (1 << 3); } else { PORTH &= ~(1 << 3); } } DcsBios::IntegerBuffer clA4Buffer(0x10d4, 0x0008, 3, onClA4Change);
+void onClB1Change(unsigned int newValue) { if (newValue == 1) { PORTH |= (1 << 4); } else { PORTH &= ~(1 << 4); } } DcsBios::IntegerBuffer clB1Buffer(0x10d4, 0x0010, 4, onClB1Change);
+void onClB2Change(unsigned int newValue) { if (newValue == 1) { PORTH |= (1 << 5); } else { PORTH &= ~(1 << 5); } } DcsBios::IntegerBuffer clB2Buffer(0x10d4, 0x0020, 5, onClB2Change);
+void onClB3Change(unsigned int newValue) { if (newValue == 1) { PORTH |= (1 << 6); } else { PORTH &= ~(1 << 6); } } DcsBios::IntegerBuffer clB3Buffer(0x10d4, 0x0040, 6, onClB3Change);
+void onClB4Change(unsigned int newValue) { if (newValue == 1) { PORTB |= (1 << 4); } else { PORTB &= ~(1 << 4); } } DcsBios::IntegerBuffer clB4Buffer(0x10d4, 0x0080, 7, onClB4Change);
+void onClC1Change(unsigned int newValue) { if (newValue == 1) { PORTB |= (1 << 5); } else { PORTB &= ~(1 << 5); } } DcsBios::IntegerBuffer clC1Buffer(0x10d4, 0x0100, 8, onClC1Change);
+void onClC2Change(unsigned int newValue) { if (newValue == 1) { PORTB |= (1 << 6); } else { PORTB &= ~(1 << 6); } } DcsBios::IntegerBuffer clC2Buffer(0x10d4, 0x0200, 9, onClC2Change);
+void onClC3Change(unsigned int newValue) { if (newValue == 1) { PORTJ |= (1 << 1); } else { PORTJ &= ~(1 << 1); } } DcsBios::IntegerBuffer clC3Buffer(0x10d4, 0x0400, 10, onClC3Change);
+void onClC4Change(unsigned int newValue) { if (newValue == 1) { PORTJ |= (1 << 0); } else { PORTJ &= ~(1 << 0); } } DcsBios::IntegerBuffer clC4Buffer(0x10d4, 0x0800, 11, onClC4Change);
+void onClD1Change(unsigned int newValue) { if (newValue == 1) { PORTH |= (1 << 1); } else { PORTH &= ~(1 << 1); } } DcsBios::IntegerBuffer clD1Buffer(0x10d4, 0x1000, 12, onClD1Change);
+void onClD2Change(unsigned int newValue) { if (newValue == 1) { PORTH |= (1 << 0); } else { PORTH &= ~(1 << 0); } } DcsBios::IntegerBuffer clD2Buffer(0x10d4, 0x2000, 13, onClD2Change);
+void onClD3Change(unsigned int newValue) { if (newValue == 1) { PORTD |= (1 << 3); } else { PORTD &= ~(1 << 3); } } DcsBios::IntegerBuffer clD3Buffer(0x10d4, 0x4000, 14, onClD3Change);
+void onClD4Change(unsigned int newValue) { if (newValue == 1) { PORTF |= (1 << 0); } else { PORTF &= ~(1 << 0); } } DcsBios::IntegerBuffer clD4Buffer(0x10d4, 0x8000, 15, onClD4Change);
+void onClE1Change(unsigned int newValue) { if (newValue == 1) { PORTF |= (1 << 1); } else { PORTF &= ~(1 << 1); } } DcsBios::IntegerBuffer clE1Buffer(0x10d6, 0x0001, 0, onClE1Change);
+void onClE2Change(unsigned int newValue) { if (newValue == 1) { PORTF |= (1 << 2); } else { PORTF &= ~(1 << 2); } } DcsBios::IntegerBuffer clE2Buffer(0x10d6, 0x0002, 1, onClE2Change);
+void onClE3Change(unsigned int newValue) { if (newValue == 1) { PORTF |= (1 << 3); } else { PORTF &= ~(1 << 3); } } DcsBios::IntegerBuffer clE3Buffer(0x10d6, 0x0004, 2, onClE3Change);
+void onClE4Change(unsigned int newValue) { if (newValue == 1) { PORTF |= (1 << 4); } else { PORTF &= ~(1 << 4); } } DcsBios::IntegerBuffer clE4Buffer(0x10d6, 0x0008, 3, onClE4Change);
+void onClF1Change(unsigned int newValue) { if (newValue == 1) { PORTF |= (1 << 5); } else { PORTF &= ~(1 << 5); } } DcsBios::IntegerBuffer clF1Buffer(0x10d6, 0x0010, 4, onClF1Change);
+void onClF2Change(unsigned int newValue) { if (newValue == 1) { PORTF |= (1 << 6); } else { PORTF &= ~(1 << 6); } } DcsBios::IntegerBuffer clF2Buffer(0x10d6, 0x0020, 5, onClF2Change);
+void onClF3Change(unsigned int newValue) { if (newValue == 1) { PORTF |= (1 << 7); } else { PORTF &= ~(1 << 7); } } DcsBios::IntegerBuffer clF3Buffer(0x10d6, 0x0040, 6, onClF3Change);
+void onClF4Change(unsigned int newValue) { if (newValue == 1) { PORTK |= (1 << 0); } else { PORTK &= ~(1 << 0); } } DcsBios::IntegerBuffer clF4Buffer(0x10d6, 0x0080, 7, onClF4Change);
+void onClG1Change(unsigned int newValue) { if (newValue == 1) { PORTK |= (1 << 1); } else { PORTK &= ~(1 << 1); } } DcsBios::IntegerBuffer clG1Buffer(0x10d6, 0x0100, 8, onClG1Change);
+void onClG2Change(unsigned int newValue) { if (newValue == 1) { PORTK |= (1 << 2); } else { PORTK &= ~(1 << 2); } } DcsBios::IntegerBuffer clG2Buffer(0x10d6, 0x0200, 9, onClG2Change);
+void onClG3Change(unsigned int newValue) { if (newValue == 1) { PORTK |= (1 << 3); } else { PORTK &= ~(1 << 3); } } DcsBios::IntegerBuffer clG3Buffer(0x10d6, 0x0400, 10, onClG3Change);
+void onClG4Change(unsigned int newValue) { if (newValue == 1) { PORTK |= (1 << 4); } else { PORTK &= ~(1 << 4); } } DcsBios::IntegerBuffer clG4Buffer(0x10d6, 0x0800, 11, onClG4Change);
+void onClH1Change(unsigned int newValue) { if (newValue == 1) { PORTK |= (1 << 5); } else { PORTK &= ~(1 << 5); } } DcsBios::IntegerBuffer clH1Buffer(0x10d6, 0x1000, 12, onClH1Change);
+void onClH2Change(unsigned int newValue) { if (newValue == 1) { PORTK |= (1 << 6); } else { PORTK &= ~(1 << 6); } } DcsBios::IntegerBuffer clH2Buffer(0x10d6, 0x2000, 13, onClH2Change);
+void onClH3Change(unsigned int newValue) { if (newValue == 1) { PORTK |= (1 << 7); } else { PORTK &= ~(1 << 7); } } DcsBios::IntegerBuffer clH3Buffer(0x10d6, 0x4000, 14, onClH3Change);
+void onClH4Change(unsigned int newValue) { if (newValue == 1) { PORTD |= (1 << 2); } else { PORTD &= ~(1 << 2); } } DcsBios::IntegerBuffer clH4Buffer(0x10d6, 0x8000, 15, onClH4Change);
+void onClI1Change(unsigned int newValue) { if (newValue == 1) { PORTD |= (1 << 1); } else { PORTD &= ~(1 << 1); } } DcsBios::IntegerBuffer clI1Buffer(0x10d8, 0x0001, 0, onClI1Change);
+void onClI2Change(unsigned int newValue) { if (newValue == 1) { PORTD |= (1 << 0); } else { PORTD &= ~(1 << 0); } } DcsBios::IntegerBuffer clI2Buffer(0x10d8, 0x0002, 1, onClI2Change);
+void onClI3Change(unsigned int newValue) { if (newValue == 1) { PORTA |= (1 << 0); } else { PORTA &= ~(1 << 0); } } DcsBios::IntegerBuffer clI3Buffer(0x10d8, 0x0004, 2, onClI3Change);
+void onClI4Change(unsigned int newValue) { if (newValue == 1) { PORTA |= (1 << 1); } else { PORTA &= ~(1 << 1); } } DcsBios::IntegerBuffer clI4Buffer(0x10d8, 0x0008, 3, onClI4Change);
+void onClJ1Change(unsigned int newValue) { if (newValue == 1) { PORTA |= (1 << 2); } else { PORTA &= ~(1 << 2); } } DcsBios::IntegerBuffer clJ1Buffer(0x10d8, 0x0010, 4, onClJ1Change);
+void onClJ2Change(unsigned int newValue) { if (newValue == 1) { PORTA |= (1 << 3); } else { PORTA &= ~(1 << 3); } } DcsBios::IntegerBuffer clJ2Buffer(0x10d8, 0x0020, 5, onClJ2Change);
+void onClJ3Change(unsigned int newValue) { if (newValue == 1) { PORTA |= (1 << 4); } else { PORTA &= ~(1 << 4); } } DcsBios::IntegerBuffer clJ3Buffer(0x10d8, 0x0040, 6, onClJ3Change);
+void onClJ4Change(unsigned int newValue) { if (newValue == 1) { PORTA |= (1 << 5); } else { PORTA &= ~(1 << 5); } } DcsBios::IntegerBuffer clJ4Buffer(0x10d8, 0x0080, 7, onClJ4Change);
+void onClK1Change(unsigned int newValue) { if (newValue == 1) { PORTA |= (1 << 6); } else { PORTA &= ~(1 << 6); } } DcsBios::IntegerBuffer clK1Buffer(0x10d8, 0x0100, 8, onClK1Change);
+void onClK2Change(unsigned int newValue) { if (newValue == 1) { PORTA |= (1 << 7); } else { PORTA &= ~(1 << 7); } } DcsBios::IntegerBuffer clK2Buffer(0x10d8, 0x0200, 9, onClK2Change);
+void onClK3Change(unsigned int newValue) { if (newValue == 1) { PORTC |= (1 << 7); } else { PORTC &= ~(1 << 7); } } DcsBios::IntegerBuffer clK3Buffer(0x10d8, 0x0400, 10, onClK3Change);
+void onClK4Change(unsigned int newValue) { if (newValue == 1) { PORTC |= (1 << 6); } else { PORTC &= ~(1 << 6); } } DcsBios::IntegerBuffer clK4Buffer(0x10d8, 0x0800, 11, onClK4Change);
+void onClL1Change(unsigned int newValue) { if (newValue == 1) { PORTC |= (1 << 5); } else { PORTC &= ~(1 << 5); } } DcsBios::IntegerBuffer clL1Buffer(0x10d8, 0x1000, 12, onClL1Change);
+void onClL2Change(unsigned int newValue) { if (newValue == 1) { PORTC |= (1 << 4); } else { PORTC &= ~(1 << 4); } } DcsBios::IntegerBuffer clL2Buffer(0x10d8, 0x2000, 13, onClL2Change);
+void onClL3Change(unsigned int newValue) { if (newValue == 1) { PORTC |= (1 << 3); } else { PORTC &= ~(1 << 3); } } DcsBios::IntegerBuffer clL3Buffer(0x10d8, 0x4000, 14, onClL3Change);
+void onClL4Change(unsigned int newValue) { if (newValue == 1) { PORTC |= (1 << 2); } else { PORTC &= ~(1 << 2); } } DcsBios::IntegerBuffer clL4Buffer(0x10d8, 0x8000, 15, onClL4Change);
+
+void setup() {
+  DcsBios::setup();
+}
+
+void loop() {
+  DcsBios::loop();
+}

src/DcsBios.h

@@ -14,6 +14,7 @@
 #include "internal/ExportStreamListener.h"
 #include "internal/PollingInput.h"
 #include "internal/Protocol.h"
+#include "internal/Protocol.cpp.inc" // Needs to be a .cpp.inc to allow DCSBIOS_INCOMING_DATA_BUFFER_SIZE
 #include "internal/Addresses.h"
 
 

src/internal/DcsBiosNgRS485Slave.cpp.inc

@@ -107,7 +107,12 @@ namespace DcsBios {
 			case RX_WAIT_DATA:
 				rxtx_len--;
 				if (rx_datatype == RXDATA_DCSBIOS_EXPORT) {
-					parser.processCharISR(c);
+					if (rxtx_len <= parser.incomingDataBuffer.availableForWrite()) {
+						parser.processCharISR(c);
+					} else {
+						last_rx_time = micros();
+						state = SYNC;
+					}
 				}
 				if (rxtx_len == 0) {
 					state = RX_WAIT_CHECKSUM;
@@ -240,6 +245,14 @@ namespace DcsBios {
 	void loop() {
 		PollingInput::pollInputs();
 		ExportStreamListener::loopAll();
+
+		// Process incoming data outside of ISR
+		#ifdef DCSBIOS_DEFER_RS485_PROCESSING
+		if (!parser.incomingDataBuffer.isEmpty()) {
+			unsigned char nextByte = parser.incomingDataBuffer.get();
+			parser.processChar(nextByte);
+		}
+		#endif
 	}
 
 	void resetAllStates() {

src/internal/Protocol.cpp → src/internal/Protocol.cpp.inc

@@ -20,6 +20,9 @@ namespace DcsBios {
 	*/
 	void ProtocolParser::processCharISR(unsigned char c) {
 		incomingDataBuffer.put(c);
+
+		// For some reason RS485 slaves cannot process data here, while it works over USB. Perhaps due to the additonal overhead of the RS485 state machine? If DCSBIOS_RS485_SLAVE is defined, the processing is deferred to loop().
+		#ifndef DCSBIOS_DEFER_RS485_PROCESSING
 		if (processingData) return;
 
 		processingData = true;
@@ -31,10 +34,8 @@ namespace DcsBios {
 			unsigned char nextByte = incomingDataBuffer.get();
 			interrupts();
 			processChar(nextByte);
-#ifdef DCSBIOS_RS485_SLAVE
-			noInterrupts();
-#endif
 		}
+		#endif
 	}
 
 	void ProtocolParser::processChar(unsigned char c) {

src/internal/Protocol.h

@@ -9,6 +9,10 @@
 #define DCSBIOS_STATE_DATA_LOW 5
 #define DCSBIOS_STATE_DATA_HIGH 6
 
+#ifndef DCSBIOS_INCOMING_DATA_BUFFER_SIZE
+#define DCSBIOS_INCOMING_DATA_BUFFER_SIZE 64
+#endif
+
 #include "ExportStreamListener.h"
 #include "RingBuffer.h"
 
@@ -23,9 +27,10 @@ namespace DcsBios {
 			volatile unsigned char sync_byte_count;
 
 			ExportStreamListener* startESL;
-			RingBuffer<64> incomingDataBuffer;
 			volatile bool processingData;
 		public:
+			RingBuffer<DCSBIOS_INCOMING_DATA_BUFFER_SIZE> incomingDataBuffer;
+
 			void processChar(unsigned char c);
 			void processCharISR(unsigned char c);
 			ProtocolParser();

src/internal/RingBuffer.h

@@ -16,6 +16,7 @@ namespace DcsBios {
 		__attribute__((always_inline)) uint8_t get() { uint8_t ret = buffer[readpos]; readpos = ++readpos % SIZE; return ret; }
 		__attribute__((always_inline)) uint8_t getLength() { return (uint8_t)(writepos - readpos) % SIZE; }
 		__attribute__((always_inline)) void clear() { readpos = 0; writepos = 0; }
+		__attribute__((always_inline)) uint8_t availableForWrite() { return SIZE - getLength() - 1; }
 	};
 }