Added support for decoding of "special" NEC repeats

Author: ArminJo

README.md

@@ -7,6 +7,7 @@ This library enables you to send and receive using infra-red signals on an Ardui
 [![Commits since latest](https://img.shields.io/github/commits-since/Arduino-IRremote/Arduino-IRremote/latest)](https://github.com/Arduino-IRremote/Arduino-IRremote/commits/master)
 [![Installation instructions](https://www.ardu-badge.com/badge/IRremote.svg?)](https://www.ardu-badge.com/IRremote)
 [![LibraryBuild](https://github.com/Arduino-IRremote/Arduino-IRremote/workflows/LibraryBuild/badge.svg)](https://github.com/Arduino-IRremote/Arduino-IRremote/actions)
+[![Stand With Ukraine](https://raw.githubusercontent.com/vshymanskyy/StandWithUkraine/main/badges/StandWithUkraine.svg)](https://stand-with-ukraine.pp.ua)
 
 Available as [Arduino library "IRremote"](https://www.arduinolibraries.info/libraries/i-rremote).
 
@@ -384,19 +385,19 @@ Modify them by enabling / disabling them, or change the values if applicable.
 | Name | Default value | Description |
 |-|-|-|
 | `RAW_BUFFER_LENGTH` |  100 | Buffer size of raw input buffer. Must be even! 100 is sufficient for *regular* protocols of up to 48 bits, but for most air conditioner protocols a value of up to 750 is required. Use the ReceiveDump example to find smallest value for your requirements. |
-| `IR_SEND_PIN` |  disabled | If specified (as constant), reduces program size and improves send timing for AVR. If you want to use a runtime variable send pin e.g. with `setSendPin(uint8_t aSendPinNumber)` , you must disable this macro. |
-| `SEND_PWM_BY_TIMER` |  disabled | Disable carrier PWM generation in software and use (restricted) hardware PWM. Enabled for ESP32 and RP2040 in all examples. |
-| `USE_NO_SEND_PWM` |  disabled | Use no carrier PWM, just simulate an **active low** receiver signal. Overrides `SEND_PWM_BY_TIMER` definition. |
-| `USE_OPEN_DRAIN_OUTPUT_FOR_SEND_PIN` |  disabled | Use or simulate open drain output mode at send pin. **Attention, active state of open drain is LOW**, so connect the send LED between positive supply and send pin! |
-| `EXCLUDE_EXOTIC_PROTOCOLS` |  disabled | If activated, BOSEWAVE, WHYNTER and LEGO_PF are excluded in `decode()` and in sending with `IrSender.write()`. Saves up to 650 bytes program memory. |
-| `EXCLUDE_UNIVERSAL_PROTOCOLS` |  disabled | If activated, the universal decoder for pulse distance protocols and decodeHash (special decoder for all protocols) are excluded in `decode()`. Saves up to 1000 bytes program memory. |
+| `EXCLUDE_UNIVERSAL_PROTOCOLS` |  disabled | Excludes the universal decoder for pulse distance protocols and decodeHash (special decoder for all protocols) from `decode()`. Saves up to 1000 bytes program memory. |
 | `DECODE_<Protocol name>` |  all | Selection of individual protocol(s) to be decoded. You can specify multiple protocols. See [here](https://github.com/Arduino-IRremote/Arduino-IRremote/blob/master/src/IRremote.hpp#L98-L121)  |
 | `MARK_EXCESS_MICROS` |  20 | MARK_EXCESS_MICROS is subtracted from all marks and added to all spaces before decoding, to compensate for the signal forming of different IR receiver modules. |
 | `RECORD_GAP_MICROS` |  5000 | Minimum gap between IR transmissions, to detect the end of a protocol.<br/>Must be greater than any space of a protocol e.g. the NEC header space of 4500 µs.<br/>Must be smaller than any gap between a command and a repeat; e.g. the retransmission gap for Sony is around 24 ms.<br/>Keep in mind, that this is the delay between the end of the received command and the start of decoding. |
-| `FEEDBACK_LED_IS_ACTIVE_LOW` |  disabled | Required on some boards (like my BluePill and my ESP8266 board), where the feedback LED is active low. |
-| `NO_LED_FEEDBACK_CODE` |  disabled | This completely disables the LED feedback code for send and receive, thus saving around 100 bytes program memory for receiving, around 500 bytes for sending and halving the receiver ISR processing time. |
 | `IR_INPUT_IS_ACTIVE_HIGH` |  disabled | Enable it if you use a RF receiver, which has an active HIGH output signal. |
+| `IR_SEND_PIN` |  disabled | If specified (as constant), reduces program size and improves send timing for AVR. If you want to use a runtime variable send pin e.g. with `setSendPin(uint8_t aSendPinNumber)` , you must disable this macro. |
+| `SEND_PWM_BY_TIMER` |  disabled | Disables carrier PWM generation in software and use (restricted) hardware PWM. Enabled for ESP32 and RP2040 in all examples. |
+| `USE_NO_SEND_PWM` |  disabled | Uses no carrier PWM, just simulate an **active low** receiver signal. Overrides `SEND_PWM_BY_TIMER` definition. |
 | `IR_SEND_DUTY_CYCLE_PERCENT` |  30 | Duty cycle of IR send signal. |
+| `USE_OPEN_DRAIN_OUTPUT_FOR_SEND_PIN` |  disabled | Uses or simulates open drain output mode at send pin. **Attention, active state of open drain is LOW**, so connect the send LED between positive supply and send pin! |
+| `EXCLUDE_EXOTIC_PROTOCOLS` |  disabled | Excludes BOSEWAVE, WHYNTER and LEGO_PF from `decode()` and from sending with `IrSender.write()`. Saves up to 650 bytes program memory. |
+| `FEEDBACK_LED_IS_ACTIVE_LOW` |  disabled | Required on some boards (like my BluePill and my ESP8266 board), where the feedback LED is active low. |
+| `NO_LED_FEEDBACK_CODE` |  disabled | Disables the LED feedback code for send and receive. Saves around 100 bytes program memory for receiving, around 500 bytes for sending and halving the receiver ISR processing time. |
 | `MICROS_PER_TICK` |  50 | Resolution of the raw input buffer data. Corresponds to 2 pulses of each 26.3 µs at 38 kHz. |
 | `TOLERANCE_FOR_DECODERS_MARK_OR_SPACE_MATCHING` | 25 | Relative tolerance (in percent) for matchTicks(), matchMark() and matchSpace() functions used for protocol decoding. |
 | `DEBUG` | disabled | Enables lots of lovely debug output. |
@@ -407,7 +408,8 @@ These next macros for **TinyIRReceiver** must be defined in your program before
 |-|-|-|
 | `IR_INPUT_PIN` | 2 | The pin number for TinyIRReceiver IR input, which gets compiled in. |
 | `IR_FEEDBACK_LED_PIN` | `LED_BUILTIN` | The pin number for TinyIRReceiver feedback LED, which gets compiled in. |
-| `NO_LED_FEEDBACK_CODE` | disabled | Enable it to disable the feedback LED function. Saves 14 bytes program memory. |
+| `NO_LED_FEEDBACK_CODE` | disabled | Disables the feedback LED function. Saves 14 bytes program memory. |
+| `DISABLE_NEC_SPECIAL_REPEAT_SUPPORT` | disabled | Disables the detection of full NEC frame repeats. Saves 40 bytes program memory. |
 
 ### Changing include (*.h) files with Arduino IDE
 First, use *Sketch > Show Sketch Folder (Ctrl+K)*.<br/>

changelog.md

@@ -10,6 +10,7 @@ See also the commit log at github: https://github.com/Arduino-IRremote/Arduino-I
 - Fixed potential bug in SendBiphase data for 1 bit.
 - Fixed bug in send for RP4020.
 - Fixed pin mapping problems especially for Teensy 2.0.
+- Added support for decoding of "special" NEC repeats.
 
 ## 3.7.1
 - SendRaw now supports bufferlenght > 255.

examples/AllProtocols/AllProtocols.ino

@@ -130,7 +130,7 @@ void setup() {
     IrReceiver.begin(IR_RECEIVE_PIN, ENABLE_LED_FEEDBACK);
 
     Serial.print(F("Ready to receive IR signals of protocols: "));
-    printActiveIRProtocols(&Serial);
+    printActiveIRProtocols (&Serial);
     Serial.println(F("at pin " STR(IR_RECEIVE_PIN)));
 
 #if FLASHEND >= 0x3FFF  // For 16k flash or more, like ATtiny1604. Code does not fit in program memory of ATtiny85 etc.
@@ -267,7 +267,10 @@ void printIRResultOnLCD() {
          * Show or clear repetition flag
          */
         myLCD.setCursor(15, 1);
-        if (IrReceiver.decodedIRData.flags & (IRDATA_FLAGS_IS_REPEAT)) {
+        if (IrReceiver.decodedIRData.flags & (IRDATA_FLAGS_IS_SPECIAL_REPEAT)) {
+            myLCD.print('S');
+            return; // Since it is a repetition, printed data has not changed
+        } else if (IrReceiver.decodedIRData.flags & (IRDATA_FLAGS_IS_REPEAT)) {
             myLCD.print('R');
             return; // Since it is a repetition, printed data has not changed
         } else {

examples/IRDispatcherDemo/IRCommandDispatcher.h

@@ -82,7 +82,7 @@ class IRCommandDispatcher {
     void checkAndCallCommand(bool aCallAlsoBlockingCommands);
 
     void printIRCommandString(Print *aSerial);
-    void setRequestToStopReceived();
+    void setRequestToStopReceived(bool aRequestToStopReceived = true);
 
     uint8_t currentBlockingCommandCalled = COMMAND_INVALID; // The code for the current called command
     bool executingBlockingCommand = false;              // Lock for recursive calls of regular commands

examples/IRDispatcherDemo/IRCommandDispatcher.hpp

@@ -316,8 +316,8 @@ void IRCommandDispatcher::printIRCommandString(Print *aSerial) {
     aSerial->println(reinterpret_cast<const __FlashStringHelper*>(unknown));
 }
 
-void IRCommandDispatcher::setRequestToStopReceived() {
-    requestToStopReceived = true;
+void IRCommandDispatcher::setRequestToStopReceived(bool aRequestToStopReceived) {
+    requestToStopReceived = aRequestToStopReceived;
 }
 
 #if defined(LOCAL_DEBUG)

src/IRReceive.hpp

@@ -982,7 +982,11 @@ void printIRResultShort(Print *aSerial, IRData *aIRDataPtr, bool aPrintGap) {
         }
 
         if (aIRDataPtr->flags & IRDATA_TOGGLE_BIT_MASK) {
-            aSerial->print(F(" Toggle=1"));
+            if(aIRDataPtr->protocol == NEC) {
+                aSerial->print(F(" Special repeat"));
+            } else {
+                aSerial->print(F(" Toggle=1"));
+            }
         }
 #if defined(DECODE_DISTANCE)
         }

src/IRremoteInt.h

@@ -132,12 +132,16 @@ struct irparams_struct {
 #define IRDATA_FLAGS_IS_REPEAT          0x01
 #define IRDATA_FLAGS_IS_AUTO_REPEAT     0x02
 #define IRDATA_FLAGS_PARITY_FAILED      0x04 ///< the current (autorepeat) frame violated parity check
-#define IRDATA_TOGGLE_BIT_MASK          0x08 ///< is set if RC5 or RC6 toggle bit is set
+#define IRDATA_FLAGS_TOGGLE_BIT         0x08 ///< is set if RC5 or RC6 toggle bit is set
+#define IRDATA_FLAGS_IS_SPECIAL_REPEAT  0x08 ///< is set if we received a NEC special receive (full frame instead of repeat frame)
 #define IRDATA_FLAGS_EXTRA_INFO         0x10 ///< there is extra info not contained in address and data (e.g. Kaseikyo unknown vendor ID)
 #define IRDATA_FLAGS_WAS_OVERFLOW       0x40 ///< irparams.rawlen is 0 in this case to avoid endless OverflowFlag
 #define IRDATA_FLAGS_IS_LSB_FIRST       0x00
 #define IRDATA_FLAGS_IS_MSB_FIRST       0x80 ///< Just for info. Value is mainly determined by the protocol
 
+// deprecated
+#define IRDATA_TOGGLE_BIT_MASK          0x08 ///< is set if RC5 or RC6 toggle bit is set
+
 #define RAW_DATA_ARRAY_SIZE             ((((RAW_BUFFER_LENGTH - 2) - 1) / 64) + 1) // The -2 is for initial gap + stop bit mark, 64 mark + spaces for 32 bit.
 /**
  * Data structure for the user application, available as decodedIRData.
@@ -214,17 +218,17 @@ class IRrecv {
     /*
      * Useful info and print functions
      */
-    void printIRResultShort(Print *aSerial);
     void printIRResultMinimal(Print *aSerial);
     void printIRResultRawFormatted(Print *aSerial, bool aOutputMicrosecondsInsteadOfTicks = true);
     void printIRResultAsCVariables(Print *aSerial);
 
     /*
-     * Next 3 functions are also available as non member functions
+     * Next 4 functions are also available as non member functions
      */
+    void printIRResultShort(Print *aSerial);
     void printIRSendUsage(Print *aSerial);
-    void printActiveIRProtocols(Print *aSerial);
     const __FlashStringHelper* getProtocolString();
+    static void printActiveIRProtocols(Print *aSerial);
 
     void compensateAndPrintIRResultAsCArray(Print *aSerial, bool aOutputMicrosecondsInsteadOfTicks = true);
     void compensateAndPrintIRResultAsPronto(Print *aSerial, unsigned int frequency = 38000U);
@@ -329,11 +333,12 @@ bool MATCH_SPACE(unsigned int measured_ticks, unsigned int desired_us);
 
 int getMarkExcessMicros();
 /*
- * Next 3 functions are also available as member functions
+ * Next 4 functions are also available as member functions
  */
-void printActiveIRProtocols(Print *aSerial);
 void printIRResultShort(Print *aSerial, IRData *aIRDataPtr, bool aPrintGap);
 void printIRSendUsage(Print *aSerial, IRData *aIRDataPtr);
+const __FlashStringHelper* getProtocolString();
+void printActiveIRProtocols(Print *aSerial);
 
 /****************************************************
  * Feedback LED related functions

src/TinyIRReceiver.h

@@ -2,7 +2,7 @@
  *  TinyIRReceiver.h
  *
  *
- *  Copyright (C) 2021  Armin Joachimsmeyer
+ *  Copyright (C) 2021-2022  Armin Joachimsmeyer
  *  [email protected]
  *
  *  This file is part of IRMP https://github.com/ukw100/IRMP.
@@ -28,6 +28,8 @@
 
 #include <Arduino.h>
 
+//#define DISABLE_NEC_SPECIAL_REPEAT_SUPPORT    // Activating this disables detection of full NEC frame repeats. Saves 40 bytes program memory.
+
 #include "LongUnion.h"
 
 /** \addtogroup TinyReceiver Minimal receiver for NEC protocol
@@ -56,7 +58,9 @@ void handleReceivedTinyIRData(uint16_t aAddress, uint8_t aCommand, bool isRepeat
 #define NEC_ZERO_SPACE          NEC_UNIT
 
 #define NEC_REPEAT_HEADER_SPACE (4 * NEC_UNIT)  // 2250
-#define NEC_REPEAT_PERIOD       110000 // Not used yet - Commands are repeated every 110 ms (measured from start to start) for as long as the key on the remote control is held down.
+#define NEC_REPEAT_PERIOD       110000 // Commands are repeated every 110 ms (measured from start to start) for as long as the key on the remote control is held down.
+#define NEC_MINIMAL_DURATION    49900 // NEC_HEADER_MARK + NEC_HEADER_SPACE + 32 * 2 * NEC_UNIT + NEC_UNIT // 2.5 because we assume more zeros than ones
+#define NEC_MAXIMUM_REPEAT_SPACE (NEC_REPEAT_PERIOD - NEC_MINIMAL_DURATION + 5) // 65 ms
 
 /*
  * Macros for comparing timing values
@@ -90,7 +94,10 @@ struct TinyIRReceiverStruct {
      */
     uint32_t IRRawDataMask;
     LongUnion IRRawData;
-    bool IRRepeatDetected;
+    bool IRRepeatFrameDetected;
+#if !defined(DISABLE_NEC_SPECIAL_REPEAT_SUPPORT)
+    bool IRRepeatDistanceDetected;
+#endif
 };
 
 /*
@@ -101,7 +108,7 @@ struct TinyIRReceiverCallbackDataStruct {
     uint16_t Address;
     uint8_t Command;
     bool isRepeat;
-    bool justWritten;
+    bool justWritten; // Is set true if new data is available. Used by the main loop, to avoid multiple evaluations of the same IR frame.
 };
 
 void initPCIInterruptForTinyReceiver();

src/TinyIRReceiver.hpp

@@ -49,6 +49,8 @@
 
 #include <Arduino.h>
 
+// - DISABLE_NEC_SPECIAL_REPEAT_SUPPORT    // Activating this disables detection of full NEC frame repeats. Saves 40 bytes program memory.
+
 #include "TinyIRReceiver.h" // If not defined, it defines IR_INPUT_PIN, IR_FEEDBACK_LED_PIN and TINY_RECEIVER_USE_ARDUINO_ATTACH_INTERRUPT
 
 #include "digitalWriteFast.h"
@@ -107,9 +109,9 @@ TinyIRReceiverStruct TinyIRReceiverControl;
  * It is called every time a complete IR command or repeat was received.
  */
 #if defined(ESP32) || defined(ESP8266)
-void IRAM_ATTR handleReceivedIRData(uint16_t aAddress, uint8_t aCommand, bool isRepetition);
+extern void IRAM_ATTR handleReceivedIRData(uint16_t aAddress, uint8_t aCommand, bool isRepetition);
 #else
-void handleReceivedIRData(uint16_t aAddress, uint8_t aCommand, bool isRepetition);
+extern void handleReceivedIRData(uint16_t aAddress, uint8_t aCommand, bool isRepetition);
 #endif
 
 /**
@@ -140,7 +142,12 @@ void IRPinChangeInterruptHandler(void)
      * 1. compute microseconds after last change
      */
     uint32_t tCurrentMicros = micros();
+#if defined(DISABLE_NEC_SPECIAL_REPEAT_SUPPORT)
     uint16_t tMicrosOfMarkOrSpace = tCurrentMicros - TinyIRReceiverControl.LastChangeMicros;
+#else
+    uint32_t tMicrosOfMarkOrSpace32 = tCurrentMicros - TinyIRReceiverControl.LastChangeMicros;
+    uint16_t tMicrosOfMarkOrSpace = tMicrosOfMarkOrSpace32;
+#endif
     TinyIRReceiverControl.LastChangeMicros = tCurrentMicros;
 
     uint8_t tState = TinyIRReceiverControl.IRReceiverState;
@@ -165,6 +172,12 @@ void IRPinChangeInterruptHandler(void)
         if (tState == IR_RECEIVER_STATE_WAITING_FOR_START_MARK) {
             // We are at the beginning of the header mark, check timing at the next transition
             tState = IR_RECEIVER_STATE_WAITING_FOR_START_SPACE;
+            TinyIRReceiverControl.IRRepeatFrameDetected = false; // If we do it here, it saves 4 bytes
+#if !defined(DISABLE_NEC_SPECIAL_REPEAT_SUPPORT)
+            // Check for special repeat, where full frame is sent again after 110 ms
+            // Must use 32 bit arithmetic here!
+            TinyIRReceiverControl.IRRepeatDistanceDetected = (tMicrosOfMarkOrSpace32 < NEC_MAXIMUM_REPEAT_SPACE);
+#endif
         }
 
         else if (tState == IR_RECEIVER_STATE_WAITING_FOR_FIRST_DATA_MARK) {
@@ -176,15 +189,14 @@ void IRPinChangeInterruptHandler(void)
                 TinyIRReceiverControl.IRRawDataBitCounter = 0;
                 TinyIRReceiverControl.IRRawData.ULong = 0;
                 TinyIRReceiverControl.IRRawDataMask = 1;
-                TinyIRReceiverControl.IRRepeatDetected = false;
                 tState = IR_RECEIVER_STATE_WAITING_FOR_DATA_SPACE;
             } else if (tMicrosOfMarkOrSpace >= lowerValue25Percent(NEC_REPEAT_HEADER_SPACE)
                     && tMicrosOfMarkOrSpace <= upperValue25Percent(NEC_REPEAT_HEADER_SPACE)
                     && TinyIRReceiverControl.IRRawDataBitCounter >= NEC_BITS) {
                 /*
                  * We have a repeat header here and no broken receive before -> set repeat flag
                  */
-                TinyIRReceiverControl.IRRepeatDetected = true;
+                TinyIRReceiverControl.IRRepeatFrameDetected = true;
                 tState = IR_RECEIVER_STATE_WAITING_FOR_DATA_SPACE;
             } else {
                 // This parts are optimized by the compiler into jumps to one code :-)
@@ -240,9 +252,9 @@ void IRPinChangeInterruptHandler(void)
             if (tMicrosOfMarkOrSpace >= lowerValue50Percent(NEC_BIT_MARK)
                     && tMicrosOfMarkOrSpace <= upperValue50Percent(NEC_BIT_MARK)) {
                 /*
-                 * We have a valid mark here, check for transmission complete
+                 * We have a valid mark here, check for transmission complete, i.e. the mark of the stop bit
                  */
-                if (TinyIRReceiverControl.IRRawDataBitCounter >= NEC_BITS || TinyIRReceiverControl.IRRepeatDetected) {
+                if (TinyIRReceiverControl.IRRawDataBitCounter >= NEC_BITS || TinyIRReceiverControl.IRRepeatFrameDetected) {
                     /*
                      * Code complete -> call callback, no parity check!
                      */
@@ -264,7 +276,11 @@ void IRPinChangeInterruptHandler(void)
                      * Call user provided callback here
                      */
                     handleReceivedTinyIRData(TinyIRReceiverControl.IRRawData.UWord.LowWord,
-                            TinyIRReceiverControl.IRRawData.UByte.MidHighByte, TinyIRReceiverControl.IRRepeatDetected);
+                            TinyIRReceiverControl.IRRawData.UByte.MidHighByte, (TinyIRReceiverControl.IRRepeatFrameDetected
+#if !defined(DISABLE_NEC_SPECIAL_REPEAT_SUPPORT)
+                                    || TinyIRReceiverControl.IRRepeatDistanceDetected
+#endif
+                            ));
 
                 } else {
                     // not finished yet