ISAATBW
ISAATBW(HORPIXPAN, (startadd & 0x00000003));
ISAATBW(HORPIXPAN, ((startadd & 0x00000002) >> 1));
ISAATBW(HORPIXPAN, ((4 - (startadd & 0x00000003)) & 0x03));
ISAATBW(MODECTL, 0x01);
ISAATBW(OSCANCOLOR, 0x00);
ISAATBW(COLPLANE_EN, 0x0f);
ISAATBW(HORPIXPAN, 0x00);
ISAATBW(COLSEL, 0x00);
ISAATBW(0x16, 0x01);