The PRS component has a Sleep() and a Wakeup() API. In DeepSleep mode the fast clocks are disabled, PRS module not working any more. Those APIs guarantee a clean restart while SRam is maintained. Hibernate and Stop mode consume less energy, but require you to save PRS state into non-volatile memory. Easiest and cheapest would be to write some data into flash memory.
so, what do the API sleep() and wakeup() calls provide? I thought maybe they would store the PRS state, possibly in flash, so that it could be recovered with the Wakeup() call after coming back from the sleep.. the datasheet doesn't suggest a problem if hibernate/stop are used..
If its up to me to save the state, what values would you suggest I need to save, and where do I find them?
I don't want the PRS to continue to run after/during the sleep, just to retain its state after waking up and running once again..
The Sleep() and Wakeup() APIs store data in SRam (not in flash) which is maintained in deepsleep. I would suggest to use these, they are independent of Start() and Stop(). There are data that might get lost when power to the component ceases.