User Manual

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nRF24L01+ Product Specification

Table 28. Register map of nRF24L01+

DPL_P2

2 0 R/W Enable dynamic payload length data pipe 2.

(Requires

EN_DPL and ENAA_P2)

DPL_P1 1 0 R/W Enable dynamic payload length data pipe 1.

(Requires

EN_DPL and ENAA_P1)

DPL_P0 0 0 R/W Enable dynamic payload length data pipe 0.

(Requires

EN_DPL and ENAA_P0)

1D FEATURE R/W Feature Register

Reserved 7:3 0 R/W Only ‘00000’ allowed

EN_DPL 2 0 R/W Enables Dynamic Payload Length

EN_ACK_PAY

1 0 R/W Enables Payload with ACK

EN_DYN_ACK 0 0 R/W Enables the W_TX_PAYLOAD_NOACK command

a. Please take care when setting this parameter. If the ACK payload is more than 15 byte in 2Mbps mode the

ARD must be 500µS or more, if the ACK payload is more than 5byte in 1Mbps mode the ARD must be

500µS or more. In 250kbps mode (even when the payload is not in ACK) the ARD must be 500µS or more.

Please see section

7.4.2 on page 33 for more information.

b. This is the time the PTX is waiting for an ACK packet before a retransmit is made. The PTX is in RX mode

for 250µS (500µS in 250kbps mode) to wait for address match. If the address match is detected, it stays in

RX mode to the end of the packet, unless ARD elapses. Then it goes to standby-II mode for the rest of the

specified ARD. After the ARD it goes to TX mode and then retransmits the packet.

c. The

RX_DR IRQ is asserted by a new packet arrival event. The procedure for handling this interrupt should

be: 1) read payload through SPI, 2) clear

RX_DR IRQ, 3) read FIFO_STATUS to check if there are more

payloads available in RX FIFO, 4) if there are more data in RX FIFO, repeat from step 1).

d. If ACK packet payload is activated, ACK packets have dynamic payload lengths and the Dynamic Payload

Length feature should be enabled for pipe 0 on the PTX and PRX. This is to ensure that they receive the

ACK packets with payloads. If the ACK payload is more than 15 byte in 2Mbps mode the ARD must be

500µS or more, and if the ACK payload is more than 5 byte in 1Mbps mode the ARD must be 500µS or

more. In 250kbps mode (even when the payload is not in ACK) the ARD must be 500µS or more.

Address

(Hex)

Mnemonic Bit

Reset

Value

Type Description