Hi Telink support team,  I have encountered some other issues with b85m_module spp functions, using latest SDK3.4.2. I mounted the module with 8251ET32 chip onto
my baseboard which has an  MCU and I have setup MCU's UART port and send
one packet a time to the 8251 module. Problems: 1) As i check the spp_rx_fifo and spp_rx_fifob contents when send packets from the baseboard MCU uart port, inBDT i can see the wptr and rptr numbers increase after each e packet sending, but i cannot find any correct data in the buffer -sometimes some fixed value shows, and next time a packet sent, in the buffer after SPP_RXFIFO_SIZE skip, the same value shows. is this a  correct behavior?

2)And after i tested to change the  SPP_RXFIFO_SIZE to half ( and half) of default value ,and SPP_RXFIFO_NUM to double(and double) of default value, inBDT it seems the wptr and rptr will not continuously increase after successive key pressing, different than the default case. Is is an issue? And can i change SPP_RXFIFO_SIZE and SPP_RXFIFO_NUM in my application?

3)I have found each time(almost) when spp_rx_fifo_b area changes after packet sending from the baseboard, the spp_tx_fifo_b area also has data change ,with  SPP_TXFIFO_SIZE step ( by default it's 72 byte too, same as RX's). But I didn't set any UART data transfer loopback function, and it seems data in TX and RX FIFO are different -  and not my packet data.  Is this a correct behavior?