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#define ATA_PORT_DATA 0x000
#define ATA_PORT_ERROR 0x001
#define ATA_PORT_FEATURES 0x001
#define ATA_PORT_SCT_COUNT 0x002
#define ATA_PORT_SCT_NUMBER 0x003
#define ATA_PORT_CYL_LOW 0x004
#define ATA_PORT_CYL_HIGH 0x005
#define ATA_PORT_DRV 0x006
#define ATA_PORT_STATUS 0x007
#define ATA_PORT_COMMAND 0x007

uint16_t buffer[256];

void ata_pio28(uint16_t base, uint8_t type, uint64_t addr, uint8_t drive) {
    if(drive==ATA_MASTER) {
    outb(base+ATA_PORT_DRV, 0xE0);
    }
    else { // ATA_SLAVE
    outb(base+ATA_PORT_DRV, 0xF0);
    }

    if ((inb(base+ATA_PORT_STATUS) & 0x01)) { 
        system_ata_pio_error();
        return;
    }

    //PIO28
    outb(base+ATA_PORT_FEATURES, 0x00);
    outb(base+ATA_PORT_SCT_COUNT, 0x01);
    outb(base+ATA_PORT_SCT_NUMBER, (unsigned char)addr);
    outb(base+ATA_PORT_CYL_LOW, (unsigned char)(addr >> 8));
    outb(base+ATA_PORT_CYL_HIGH, (unsigned char)(addr >> 16));
    //type
    if(type==ATA_READ) {
    outb(base+ATA_PORT_COMMAND, 0x20);  // Send command
    }
    else {
    outb(base+ATA_PORT_COMMAND, 0x30);
    }

    //wait
    while (!(inb(base+ATA_PORT_STATUS) & 0x80)) {}  //BSY bit
    while (!(inb(base+ATA_PORT_STATUS) & 0x08)) {}  //DRQ bit

    for (int idx = 0; idx < 256; idx++)
    {
        if(type==ATA_READ) {
            buffer[idx] = inw(base + ATA_PORT_DATA);
        }
        else {
            outw(base + ATA_PORT_DATA, buffer[idx]);
        }
    }

}