NRF24L01+ working irregulary

[Fred Lamer]

Hi everyone,

I bought two NRF24L01+ off ebay a couple of week ago and started to work on them this week. I seem to have problem with establishing a reliable communication between both devices. I enabled Shockburst by setting register EN_AA all to "1" and register EN_RXADDR all to "1". I should then have auto-acknowledgement on the TX device. Both device work with the IRQ pin with external interrupt on my two MCU (ATMEGA8) and interrupt are masked with the STATUS register to show what interrupt is trigerred by the NRF. I seem to have a bad communication, but the packet still cross from the TX to the RX irregularly. I checked the value of the received packet and it is the same as the one sent., but no acknowledge received in the TX device...

Any fast thoughts on why it would do this?

Thanks, Fred

[Fred Lamer]

Hi, Sorry for the delay but I have been pretty busy in the last days. My code was pretty messed up so I am now starting back from the begining. I think my problem comes from setting the RX device's address. In the Apprendix A on page 75 in the datasheet it says you need to set a 5 bytes address in register RX_ADDR_P5, but when you look on page 60, we see that the RX_ADDR_P5 register is only 1 byte long... How do you set the RX_ADDR_P5 register correctly?

Thanks, Happy Holidays to you! Fred

[Håkon Alseth]

Hi Fred,

Thank you. Happy new year to you:)

Glad to hear that you've most likely found the source of the issue. The RF PIPES 0 and 1 are 5 byte register, while the RF PIPES 2 to 5 are 1 byte (derived from PIPE1 address).

A better overview of how the pipes are addressed is shown in the nRF24L01+ datasheet, page 40.

BR, Håkon