Implemented basic hardware master i2c support

hardware.hpp

@@ -0,0 +1,93 @@
+#pragma once
+
+#include <stdint.h>
+
+#include <util/twi.h>
+
+namespace i2c {
+
+#if defined(__AVR_ATmega1284P__)
+
+enum class Prescaler {
+	PRESCALER_1 = 0b00,
+	PRESCALER_4 = 0b01,
+	PRESCALER_16 = 0b10,
+	PRESCALER_64 = 0b11,
+};
+
+template <Prescaler Pres, uint32_t Clock>
+class Hardware {
+  public:
+	static void init()
+	{
+		TWSR = static_cast<uint8_t>(Pres);
+		TWBR = calcClock();
+	}
+
+	template <uint8_t Addr>
+	static bool start(bool read)
+	{
+		TWCR = (1 << TWINT) | (1 << TWSTA) | (1 << TWEN);
+		while (!(TWCR & (1 << TWINT)))
+			;
+
+		uint8_t status = TW_STATUS & 0xF8;
+		if (status != TW_START && status != TW_REP_START)
+			return false;
+
+		TWDR = (Addr << 1) | read;
+		TWCR = (1 << TWINT) | (1 << TWEN);
+
+		while (!(TWCR & (1 << TWINT)))
+			;
+
+		status = TW_STATUS & 0xF8;
+		if (status != TW_MT_SLA_ACK && status != TW_MR_SLA_ACK)
+			return false;
+
+		return true;
+	}
+
+	static bool write(uint8_t data)
+	{
+		TWDR = data;
+		TWCR = (1 << TWINT) | (1 << TWEN);
+
+		while (!(TWCR & (1 << TWINT)))
+			;
+
+		uint8_t status = TW_STATUS & 0xF8;
+		if (status != TW_MT_DATA_ACK)
+			return false;
+
+		return true;
+	}
+
+	template <bool LastByte = false>
+	static uint8_t read()
+	{
+		TWCR = (1 << TWINT) | (1 << TWEN) | (!LastByte << TWEA);
+		while (!(TWCR & (1 << TWINT)))
+			;
+
+		return TWDR;
+	}
+
+	static void stop()
+	{
+		TWCR = (1 << TWINT) | (1 << TWEN) | (1 << TWSTO);
+
+		while (TWCR & (1 << TWSTO))
+			;
+	}
+
+  private:
+	static constexpr uint8_t calcClock()
+	{
+		return ((F_CPU / Clock) - 16) / 2;
+	}
+};
+
+#endif
+
+} // namespace i2c

i2c.hpp

@@ -1,4 +1,39 @@
 #pragma once
 
+#include <stdint.h>
+
+#include "hardware.hpp"
+
+namespace i2c {
+
+template <class Driver>
 struct I2c {
+	static void init()
+	{
+		Driver::init();
+	}
+
+	template <uint8_t Addr>
+	static bool start(bool read)
+	{
+		return Driver::template start<Addr>(read);
+	}
+
+	static bool write(uint8_t data)
+	{
+		return Driver::write(data);
+	}
+
+	template <bool LastByte = false>
+	static uint8_t read()
+	{
+		return Driver::template read<LastByte>();
+	}
+
+	static void stop()
+	{
+		Driver::stop();
+	}
 };
+
+} // namespace i2c