nRF24l01 receiver changes values

[basilalattar]

Hello, 

I am building a wireless sensor network for my coffee business, I am using a raspberry pi as the gateway with nrf24l01 connected to it, I have a bunch of sensor nodes scattered around creating the place, the values that the sensors are reading are all correct(checked on serial monitor), I collect the data, store in an array and send the array over to the gateway, what happens is that every couple of minutes, the third value in the payload acts like a floated value (not equal to the value on the serial monitor), can anyone help me out with this issue. 

I am sure that my pcb and wiring is correct and I think the problem is with the software, I am using rf24 and rf24network libraries.

please let me now if codes and schematics are required for the assistance, ill be more than happy to provide them.

[Håkon Alseth]

Hi,

 

At what point does the data get corrupted?

Is it on the PTX side, PRX side, or on the respective host controllers?

 

Do you use 16 bit CRC?

 

Kind regards,

Håkon

[basilalattar]

The data gets corrupted at the receiver side every other transmission. 

I guess I am not because I am not familiar with what a CRC is, can you please elaborate more on that. 

Thank you for your reply.

[Håkon Alseth]

Hi,

 

If you look at the datasheet (https://infocenter.nordicsemi.com/pdf/nRF24L01P_PS_v1.0.pdf?cp=11_4_0_0), chapter 9, you can see the register map.

Its important that you try to setup the nRF's to use 2 byte CRC for best possible data integrity on-air.

 

That being said; if every other transmission is corrupted, the issue is usually elsewhere. Try changing the RF address (remember: config must match on both sides!) and RF frequency.

 

Kind regards,

Håkon

[basilalattar]

It turned out to be a noise problem, I twisted the VCC and ground wires in pairs and the MOSI/MISO as well. 

I have another question that is irrelevant to this problem, it concerns the rf24 and rf24network libraries if you are familiar with them, is the dynamic payload enabled by default in the libraries or should I enable it in the code. 

Thank you again Håkon for the help.

[Håkon Alseth]

I'm glad to hear that you found the source of the issue!

Kind regards,

Håkon