From 011204472a661c82c4ddbfd3786a78031fa0f4fd Mon Sep 17 00:00:00 2001
From: N-Storm <nstorm0.0@gmail.com>
Date: Tue, 2 Apr 2019 13:50:51 +0300
Subject: [PATCH] Alternative ESP8266 bitbang carrirer generation method

---
 IRSender.h             | 12 ++++++++++
 IRSenderESP8266Alt.cpp | 51 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 63 insertions(+)
 create mode 100644 IRSenderESP8266Alt.cpp

diff --git a/IRSender.h b/IRSender.h
index 03800c8..4586c89 100644
--- a/IRSender.h
+++ b/IRSender.h
@@ -83,6 +83,18 @@ class IRSenderESP8266 : public IRSender
   protected:
     uint32_t _halfPeriodicTime;
 };
+
+class IRSenderESP8266Alt : public IRSender
+{
+  public:
+    IRSenderESP8266Alt(uint8_t pin);
+    void setFrequency(int frequency);
+    void space(int spaceLength);
+    void mark(int markLength);
+
+  protected:
+    uint32_t _halfPeriodicTime;
+};
 #endif
 
 #endif
diff --git a/IRSenderESP8266Alt.cpp b/IRSenderESP8266Alt.cpp
new file mode 100644
index 0000000..7d797e4
--- /dev/null
+++ b/IRSenderESP8266Alt.cpp
@@ -0,0 +1,51 @@
+#include <Arduino.h>
+#ifdef ESP8266
+#include <IRSender.h>
+
+// Send IR using the 'bit banging' on ESP8266 using alternative ESP.getCycleCount() method
+
+// Cycles compensation due to while cycles and polling ESP.getCycleCount()
+#define ESP8266_CYCLES_COMPENSATION 33
+
+IRSenderESP8266Alt::IRSenderESP8266Alt(uint8_t pin) : IRSender(pin)
+{
+  pinMode(_pin, OUTPUT);
+}
+
+
+void IRSenderESP8266Alt::setFrequency(int frequency)
+{
+  // Enables IR output.  The khz value controls the modulation frequency in kilohertz.
+  _halfPeriodicTime = F_CPU / (frequency * 1000 * 2); // This one stores half period time in CPU ticks
+}
+
+
+// Send an IR 'mark' symbol, i.e. transmitter ON
+void IRSenderESP8266Alt::mark(int markLength)
+{
+  long beginning = micros();
+
+  while((int)(micros() - beginning) < markLength){
+    uint32_t periodStart = ESP.getCycleCount();
+    digitalWrite(_pin, HIGH);
+    while (ESP.getCycleCount() - periodStart < _halfPeriodicTime - ESP8266_CYCLES_COMPENSATION);
+
+    periodStart = ESP.getCycleCount();
+    digitalWrite(_pin, LOW);
+    while (ESP.getCycleCount() - periodStart < _halfPeriodicTime - ESP8266_CYCLES_COMPENSATION);
+  }
+}
+
+
+// Send an IR 'space' symbol, i.e. transmitter OFF
+void IRSenderESP8266Alt::space(int spaceLength)
+{
+  digitalWrite(_pin, LOW);
+
+  if (spaceLength < 16383) {
+    delayMicroseconds(spaceLength);
+  } else {
+    delay(spaceLength/1000);
+  }
+}
+#endif