REG_PIX_REPEAT
reg = io_read(sd, REG_PIX_REPEAT);
io_write(sd, REG_PIX_REPEAT, reg);
reg = io_read(sd, REG_PIX_REPEAT);
io_write(sd, REG_PIX_REPEAT, reg);
reg = io_read(sd, REG_PIX_REPEAT);
io_write(sd, REG_PIX_REPEAT, reg);