VGA_DAC_DATA
PUTB(reg, VGA_DAC_DATA, r >> 2);
PUTB(reg, VGA_DAC_DATA, g >> 2);
PUTB(reg, VGA_DAC_DATA, b >> 2);
*r = GETB(reg, VGA_DAC_DATA) << 2;
*g = GETB(reg, VGA_DAC_DATA) << 2;
*b = GETB(reg, VGA_DAC_DATA) << 2;