Could you help me to write this code to eject the cdrom ?
void write_atapi(unsigned char bytelow, unsigned char bytehigh)
{
TRISA = 0b00000000; // All ports A are output
TRISB = 0b00000000; // All ports B are output
TRISE = 0b00000000; // All ports E are output
TRISC = 0b00000000; // All ports C are output
TRISD = 0b00000000; // All ports D are output
RA1 = 0; // CS0
RA0 = 1; // CS1
RE0 = 1; // DA0
RE1 = 1; // DA1
RE2 = 1; // DA2
PORTD = bytehigh;
PORTC = bytelow;
RA3 = 1; // W
DelayMs(1);
RA3 = 0; // W
}
void read_atapi(int cs0, int cs1, int da0, int da1, int da2, unsigned char bytelow, unsigned char bytehigh)
{
TRISA = 0b00000000; // All ports A are output
TRISB = 0b00000000; // All ports B are output
TRISE = 0b00000000; // All ports E are output
TRISC = 0b11111111; // All ports B are input
TRISD = 0b11111111; // All ports D are input
RA1 = cs0; // CS0
RA0 = cs1; // CS1
RE0 = da0; // DA0
RE1 = da1; // DA1
RE2 = da2; // DA2
RA2 = 1; // R
bytelow = PORTC;
bytehigh = PORTD;
RA2 = 0; // R
}
void check_status()
{
unsigned char bytelow;
unsigned char bytehigh;
while(1)
{
read_atapi(1, 0, 1, 1, 1, bytelow, bytehigh): //try 10011
if (bytelow == 7)
DelayMs(1);
else if (bytelow == 3)
DelayMs(1);
else break;
}
}
void open_tray()
{
check_status();
write_atapi(0x1e, 0x00);
write_atapi(0x00, 0x00);
write_atapi(0x00, 0x00);
write_atapi(0x00, 0x00);
write_atapi(0x00, 0x00);
write_atapi(0x00, 0x00);
check_status();
write_atapi(0x1b, 0x00);
write_atapi(0x00, 0x00);
write_atapi(0x02, 0x00);
write_atapi(0x00, 0x00);
write_atapi(0x00, 0x00);
write_atapi(0x00, 0x00);
}
void cdrom()
{
RA5 = 1; // Reset high
open_tray();
}
Andrea Ciuffoli
www.audiodesignguide.com
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