Frame Reception (RX_AACK)

This section describes how frames are received in the RX_AACK mode.

Note:
If needed, the RG_PHY_ED_LEVEL can be read out after reception of the frame, refer to PHY_ED_FRAME_END.

PHY_DATA_INDICATION_RX_AACK

In the RX_AACK operating mode incoming frames are checked against the address filter and for a valid FCS. If the received frame passes this checks, an optional required ACK frame is generated and sent out and also an TRX_IRQ_TRX_END interrupt is generated.

The transmission of the ACK frame starts 12 symbols after the end of the frame reception. The complete ACK frame is on air after 34 symbols (544us).

The internal timing for the ACK frame processing in RX_AACK mode is shown below:

  == RX ==:======================= TX =========================:======= RX =======
         0         12                                          34  [time / symbols]
     +---|         |---+---+---+---+---+---+---+---+---+---+---|
   --| F |---------|PR0|PR1|PR2|PR3|SFD|LEN|     ACK   |  FCS  |------------------>
     +---|         |---+---+---+---+---+---+---+---+---+---+---|
         |         |                                           |
         t0        t1                                          t2

      F = last received data byte
      PRx = Preamble for the ACK frame
      SFD, LEN, FCS = data of the ACK frame

 

inline_mscgraph_62
Code example
    /* TRX_IRQ_TRX_END occurs here */
    frm = trx_frame_read();

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