#include 
#include 

#define I2C_START 0x08
#define I2C_MT_SLA_ACK 0x18
#define I2C_MT_DATA_ACK 0x28

void I2C_Init() {
    // Set bit rate (100kHz untuk 16MHz clock)
    TWBR = 72;
    // Enable I2C
    TWCR = (1 << TWEN);
}

void I2C_Start() {
    TWCR = (1 << TWINT) | (1 << TWSTA) | (1 << TWEN);
    while (!(TWCR & (1 << TWINT)));
}

void I2C_Stop() {
    TWCR = (1 << TWINT) | (1 << TWSTO) | (1 << TWEN);
}

void I2C_Write(uint8_t data) {
    TWDR = data;
    TWCR = (1 << TWINT) | (1 << TWEN);
    while (!(TWCR & (1 << TWINT)));
}

uint8_t I2C_Read(uint8_t ack) {
    TWCR = (1 << TWINT) | (1 << TWEN) | (ack ? (1 << TWEA) : 0);
    while (!(TWCR & (1 << TWINT)));
    return TWDR;
}

// Contoh: Baca dari sensor I2C (contoh: BMP180)
void BMP180_ReadTemp() {
    I2C_Start();
    I2C_Write(0xEE); // Address BMP180 + Write
    I2C_Write(0xF4); // Register control
    I2C_Write(0x2E); // Perintah baca temperatur
    I2C_Stop();
    
    _delay_ms(5); // Tunggu konversi
    
    I2C_Start();
    I2C_Write(0xEE); // Address BMP180 + Write
    I2C_Write(0xF6); // Register data MSB
    I2C_Start();
    I2C_Write(0xEF); // Address BMP180 + Read
    uint8_t msb = I2C_Read(1); // Read dengan ACK
    uint8_t lsb = I2C_Read(0); // Read dengan NACK
    I2C_Stop();
    
    int16_t temp = (msb << 8) | lsb;
    // Process temperature data...
}
                        

#include 

// Pin definitions
#define SPI_DDR DDRB
#define SPI_PORT PORTB
#define MOSI PB3
#define MISO PB4
#define SCK PB5
#define SS PB2

void SPI_Init() {
    // Set MOSI, SCK, dan SS sebagai output
    SPI_DDR |= (1 << MOSI) | (1 << SCK) | (1 << SS);
    // Set MISO sebagai input
    SPI_DDR &= ~(1 << MISO);
    
    // Enable SPI, Master, set clock rate fck/16
    SPCR = (1 << SPE) | (1 << MSTR) | (1 << SPR0);
}

void SPI_CS_Low() {
    SPI_PORT &= ~(1 << SS);
}

void SPI_CS_High() {
    SPI_PORT |= (1 << SS);
}

uint8_t SPI_Transfer(uint8_t data) {
    // Mulai transmisi
    SPDR = data;
    // Tunggu transmisi selesai
    while (!(SPSR & (1 << SPIF)));
    // Return data yang diterima
    return SPDR;
}

// Contoh: Baca/write ke SPI device (contoh: SD card, flash memory)
void SPI_Example() {
    SPI_Init();
    SPI_CS_Low();
    
    // Kirim command (contoh: read status register)
    SPI_Transfer(0x05);
    // Baca status
    uint8_t status = SPI_Transfer(0x00);
    
    SPI_CS_High();
    
    // Process status data...
}

// Contoh dengan sensor SPI (contoh: MAX6675 - Thermocouple)
float MAX6675_ReadTemp() {
    SPI_CS_Low();
    _delay_us(1);
    
    // Baca 16-bit data
    uint8_t high_byte = SPI_Transfer(0x00);
    uint8_t low_byte = SPI_Transfer(0x00);
    
    SPI_CS_High();
    
    // Combine bytes
    uint16_t data = (high_byte << 8) | low_byte;
    
    // Check error bit (D2)
    if (data & 0x04) {
        return -1.0; // Error
    }
    
    // Extract temperature (D15-D3)
    data = data >> 3;
    return data * 0.25; // Convert to Celsius
}