From 420d1ac7435b777444fe366d789b5db1f7c3d70d Mon Sep 17 00:00:00 2001
From: N-Storm <nstorm0.0@gmail.com>
Date: Tue, 2 Apr 2019 13:38:32 +0300
Subject: [PATCH] New bitbang method for ESP8266 using built-in startWaveform()
 function (more accurate carrier generation -> better range)

---
 IRSender.h          | 13 +++++++++++++
 IRSenderESP8266.cpp | 45 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 58 insertions(+)
 create mode 100644 IRSenderESP8266.cpp

diff --git a/IRSender.h b/IRSender.h
index a6bb13c..03800c8 100644
--- a/IRSender.h
+++ b/IRSender.h
@@ -8,6 +8,7 @@
 
 #ifdef ESP8266
 #include <IRsend.h>  // From IRremoteESP8266 library
+#include <stdint.h>
 #endif
 
 class IRSender
@@ -70,6 +71,18 @@ class IRSenderIRremoteESP8266 : public IRSender
   private:
     IRsend _ir;
 };
+
+class IRSenderESP8266 : public IRSender
+{
+  public:
+    IRSenderESP8266(uint8_t pin);
+    void setFrequency(int frequency);
+    void space(int spaceLength);
+    void mark(int markLength);
+
+  protected:
+    uint32_t _halfPeriodicTime;
+};
 #endif
 
 #endif
diff --git a/IRSenderESP8266.cpp b/IRSenderESP8266.cpp
new file mode 100644
index 0000000..f199bc7
--- /dev/null
+++ b/IRSenderESP8266.cpp
@@ -0,0 +1,45 @@
+#include <Arduino.h>
+#ifdef ESP8266
+#include <IRSender.h>
+#include <core_esp8266_waveform.h>
+
+// Send IR using the 'bit banging' with startWaveform function on ESP8266 etc.
+
+IRSenderESP8266::IRSenderESP8266(uint8_t pin) : IRSender(pin)
+{
+  pinMode(_pin, OUTPUT);
+}
+
+
+void IRSenderESP8266::setFrequency(int frequency)
+{
+  // Enables IR output.  The khz value controls the modulation frequency in kilohertz.
+  _halfPeriodicTime = 500/frequency; // T = 1/f but we need T/2 in microsecond and f is in kHz
+}
+
+
+// Send an IR 'mark' symbol, i.e. transmitter ON
+void IRSenderESP8266::mark(int markLength)
+{
+  long beginning = micros();
+
+  startWaveform(_pin, _halfPeriodicTime, _halfPeriodicTime, markLength);
+  while((int)(micros() - beginning) < markLength);
+
+  stopWaveform(_pin);
+  digitalWrite(_pin, LOW);
+}
+
+
+// Send an IR 'space' symbol, i.e. transmitter OFF
+void IRSenderESP8266::space(int spaceLength)
+{
+  digitalWrite(_pin, LOW);
+
+  if (spaceLength < 16383) {
+    delayMicroseconds(spaceLength);
+  } else {
+    delay(spaceLength/1000);
+  }
+}
+#endif