Hi: I develop my project with gazell, Device can keep send to host,but host can't keep send to device(I'm not mean for host sent ack to device). In my program, I use "nrf_gzll_add_packet_to_tx_fifo" in while(1) of host,and I use "nrf_gzll_fetch_packet_from_rx_fifo" in while(1) of device. Thanks.