My project uses ESB for communication. In our hardware design, nrf5340 + FEM is used. Nrf5340 uses two GPIO link FEM chips to switch between PA mode and LNA mode.
I use DPPI to link the PUBLISH_RXREADY and PUBLISH_TXREADY of gpiote and radio. When PUBLISH_RXREADY or PUBLISH_TXREADY is triggered respectively, the corresponding PIN controls the FEM to switch between TX mode and RX mode.
When I noticed the FEM chip I used, it takes a typical time of 500ns to switch between TX mode and RX mode (RX to TX transition time : 10% to 90% RF
50% VCTX to 90% RF).
I would like to know, if I use dppi, what is the time between the PIN level change caused by PUBLISH_TXREADY and the sending of the Radio packet?
I am worried that if this time is less than 500ns of the FEM's mode switching time, the radio data will be sent out before the fem enters the tx mode.
Am I misunderstanding somewhere.
