Auto ACK packets in multiceiver mode

[laneh]

Figure 7 of the nRF24L01 data says ACK payloads must be loaded in advance to the automatic ACK transmission. I wish to make the ACK data packet dependent on what is received, so my question is this: can I load the ACK payload FIFO after receiving a packet, rather than before? If not, can I do this by manually sending the ACK packet+data? 

[Kenneth]

can I load the ACK payload FIFO after receiving a packet, rather than before?

In such case due to the time it will take to read out the received packet and write the ACK packet, it will not be attached to the current packet, but the transmitter will need to send a second packet to fetch the ACK packet. 

If not, can I do this by manually sending the ACK packet+data? 

You can disable the hardware ACK, and for instance do this manually in software by re-configure the radio from PTX to PRX etc between each transmission, however that will cause more work for the MCU.