GCT_ID_BITMASK
WGfx(ba, GCT_ID_BITMASK, 0xff);
WGfx(ba, GCT_ID_BITMASK, 0xFF);
WGfx(ba, GCT_ID_BITMASK, 0xFF);
WGfx(ba, GCT_ID_BITMASK, 0xff);
WGfx(ba, GCT_ID_BITMASK, 0xff);
WGfx (ba, GCT_ID_BITMASK, 0xff);
regs->grf[GCT_ID_BITMASK] = 0xff;