NRF52811-QCAA-R datasheet(188/444 Pages) NORDIC

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Peripherals

PAYLOAD

CRC

RXDISABLE

TXRU

S0 L S1

PAYLOAD

TIFS

Change to SHORTS and

TIFS OK

Change to MODE OK

Figure 69: IFS timing detail

The TIFS duration starts after the last bit on air (just before the END event), and elapses with first bit being

transmitted on air (just after READY event).

TIFS is only enforced if the shortcuts END-to-DISABLE and DISABLED-to-TXEN or END-to-DISABLE and

DISABLED-to-RXEM are enabled. TIFS is qualified for use when MODE is either Ble_1Mbit, Ble_2Mbit,

Ble_LR125Kbit, Ble_LR500Kbit, or Ieee802154_250Kbit, using the default ramp-up mode. SHORTS and TIFS

are not double-buffered, and can be updated at any point in time before the last bit on air is received. The

MODE register is double-buffered and sampled at the TXEN or RXEN task.

6.14.10 Device address match

The device address match feature is tailored for address whitelisting in Bluetooth® low energy and similar

implementations.

This feature enables on-the-fly device address matching while receiving a packet on air. This feature only

works in receive mode and when the RADIO is configured for little endian, see PCNF1.ENDIAN.

The device address match unit assumes that the first 48 bits of the payload are the device address and

that bit number 6 in S0 is the TxAdd bit. See the Bluetooth® Core Specification for more information about

device addresses, TxAdd, and whitelisting.

The RADIO is able to listen for eight different device addresses at the same time. These addresses are

specified in a DAB/DAP register pair, one pair per address, in addition to a TxAdd bit configured in the

DACNF register. The DAB register specifies the 32 least significant bits of the device address, while the DAP

Each of the device addresses can be individually included or excluded from the matching mechanism. This

is configured in the DACNF register.

6.14.11 Bit counter

The RADIO implements a simple counter that can be configured to generate an event after a specific

number of bits have been transmitted or received.

By using shortcuts, this counter can be started from different events generated by the RADIO and count

relative to these.

The bit counter is started by triggering the BCSTART task, and stopped by triggering the BCSTOP task. A

BCMATCH event will be generated when the bit counter has counted the number of bits specified in the

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