What is the Programmable Peripheral Bus useful for?

[Nick]

The PPB sounds like a great piece of technology but i dont see much documentation on how a user can utilize it. For example i collect data from 3 sensors at different rates. Can it be used to collect data when the ARM is in low power mode?

I guess im trying to figure out if the PPB is something that i should learn up on or if it is something that is just used by the API and low level procedures but not the application developer.

Much Thanks

[Ole Morten]

The PPI is very useful if you want to make events in one peripheral trigger tasks in another peripheral. This is extensively used inside the softdevice and in the other radio protocol implementations, to connect for example timers, encryption modules and the radio.

However, all the functionality can in principle be replicated in code, so it isn't required to use the PPI, it's more of a way to make things happen independent of code, giving for example known, constant delays, instead of being dependent on interrupt latency. For a lot of typical application tasks, it doesn't make much sense to use the PPI, but it can be useful when dealing with some of the serial interfaces. See for example the TWI module in the SDK.