94 lines
1.5 KiB
C++
94 lines
1.5 KiB
C++
#pragma once
|
|
|
|
#include <stdint.h>
|
|
|
|
#include <util/twi.h>
|
|
|
|
namespace i2c {
|
|
|
|
#if defined(__AVR_ATmega1284P__) || defined(__AVR_ATmega328P__)
|
|
|
|
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
|