BCM2835_SPI_FIFO_SIZE
bcm2835_wr_fifo_blind(bs, BCM2835_SPI_FIFO_SIZE);
bcm2835_rd_fifo_blind(bs, BCM2835_SPI_FIFO_SIZE);
bcm2835_wr_fifo_blind(bs, BCM2835_SPI_FIFO_SIZE);
bcm2835_wr_fifo_blind(bs, BCM2835_SPI_FIFO_SIZE);