Make IR timing and RX terminal state explicit

tests/arduino_stubs/Arduino.h

@@ -0,0 +1,60 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+
+class __FlashStringHelper;
+#define F(value) reinterpret_cast<const __FlashStringHelper *>(value)
+
+struct GPIO_TypeDef
+{
+    uint32_t BSRR = 0U;
+    uint32_t IDR = 0U;
+};
+
+using IRQn_Type = int;
+enum TimerFormat_t : uint8_t { TICK_FORMAT = 0, MICROSEC_FORMAT, HERTZ_FORMAT };
+
+constexpr uint8_t LOW = 0U;
+constexpr uint8_t HIGH = 1U;
+constexpr uint8_t INPUT = 0U;
+constexpr uint8_t OUTPUT = 1U;
+
+class HardwareTimer
+{
+public:
+    void pause() {}
+    void resume() {}
+    void setOverflow(uint32_t value, TimerFormat_t = TICK_FORMAT) { overflow_ = value; }
+    uint32_t getOverflow(TimerFormat_t = TICK_FORMAT) { return overflow_; }
+    uint32_t getPrescaleFactor() { return 1U; }
+    uint32_t getTimerClkFreq() { return 12000000U; }
+    void attachInterrupt(uint8_t, void (*)()) {}
+
+private:
+    uint32_t overflow_ = 1U;
+};
+
+inline GPIO_TypeDef arduinoStubPort;
+inline GPIO_TypeDef *digitalPinToPort(uint8_t) { return &arduinoStubPort; }
+inline uint16_t digitalPinToBitMask(uint8_t) { return 1U; }
+inline void pinMode(uint8_t, uint8_t) {}
+inline void digitalWrite(uint8_t, uint8_t) {}
+inline void NVIC_SetPriority(IRQn_Type, uint8_t) {}
+inline void noInterrupts() {}
+inline void interrupts() {}
+
+inline uint32_t arduinoStubMicros = 0U;
+inline uint32_t micros() { return arduinoStubMicros; }
+inline uint32_t millis() { return arduinoStubMicros / 1000U; }
+
+class Print
+{
+public:
+    template <typename T> void print(const T &) {}
+    template <typename T> void println(const T &) {}
+    void println() {}
+};
+
+using ArduinoSerialStub = Print;
+inline ArduinoSerialStub Serial;