nrf_802154_trx_receive_frame_prestarted()

void nrf_802154_trx_receive_frame_prestarted ( void )

extern

Handler called at the beginning of frame reception (earliest possible moment).

This handler is called from an ISR when:

• receive operation has been started with a call to nrf_802154_trx_receive_frame
• the RADIO peripheral detected energy on channel or started synchronizing to it.

When this handler is called following holds:

• trx module is in RXFRAME state.

Implementation of nrf_802154_trx_receive_frame_started may call:

• nrf_802154_trx_abort if current receive frame needs to be aborted (usually followed by a call moving the trx module out of FINISHED state)
• nrf_802154_trx_disable

Note

This handler may be triggered several times during receive of a preamble of a frame. It can be followed by call to nrf_802154_trx_receive_frame_started (if enabled) and then by nrf_802154_trx_receive_frame_received or nrf_802154_trx_receive_frame_crcerror, but there is possibility that it will not be followed by these calls (In case when the RADIO didn't found full preamble.). If implementation of this handler starts some activity that must be terminated by a further call, it must implement its own timeout feature.