Send and receive at the same time?

[khozDonel]

Hi Nordic Devzone,

I'm working with nrf52-PDK and Mesh SDK, I wanted to know that if it is possible to send and receive some data at the same time?

And if I can do that then is it possible to get some collision in the network?

Thank you!

[ovrebekk]

Hi

A single node can not send and receive at exactly the same time, if that is what you're asking. The radio is half duplex, and can only be in either receive or transmit mode.

The way it works in mesh is that the radio will be in receive mode whenever it doesn't have any data to send, and only switch to TX once it needs to send some data, or relay a packet from a different node. 

If two devices try to send at the same time then you might get a packet collision, yes. That said you might also get into situations where both packets are received by some other node (but not the same node obviously). 

Best regards
Torbjørn

[khozDonel]

Thank you very much for your explanation

[ovrebekk]

You welcome 

[bigturtle]

Hi everyone

What does happen if I get a packet collision ? the nrf crash or reset or something else ?

[ovrebekk]

Hi Randy

Packet collisions are perfectly normal, and won't have any adverse effect on the Nordic device. 

What ends up happening is that one or both of the packets are lost, and won't be received by any receiving devices, since the two packets are sent on top of each other. 

If one of the packets has a significantly stronger signal than the other, and is sent earlier, it has a good chance of getting through despite the collision. 

Best regards
Torbjørn