[Tinyos-devel] start/stop with lpl

[Philip Levis]

On Dec 13, 2008, at 11:48 AM, Razvan Musaloiu-E. wrote:

> Hi!
>
> On Sat, 13 Dec 2008, Philip Levis wrote:
>
>>
>> On Dec 12, 2008, at 10:10 PM, Omprakash Gnawali wrote:
>>
>>> During net2 meeting today, Razvan brought up an interesting
>>> observation. With LPL, stdcontrol.start means turn the radio off.
>>> stdcontrol.startdone means the radio has turned off. To someone who
>>> just knows that LPL means dutycycling but does not know the
>>> mechanisms, this seems opposite of what those names suggest.
>>
>> I don't understand; can you be clearer? SplitControl on what
>> component? How is the radio on without calling start?
>>
>
> The SplitControl in discussion is the one implemented by PowerCycleC  
> (which gets wired to ActiveMessageC through DefaultLplC and  
> CC2420ActiveMessageC). The confusion comes from the interaction  
> between the the SplitControl and the setLocalSleepInterval command  
> from the LowPowerListening Interface.
>
> Here are some questions that shows this.
>
>  What happens when a call to LowPowerListening.setLocalSleepInterval  
> is
>  made? Does the duty-cycles starts immediately or I still need to do  
> call
>  SplitControl.start?
>
>  If I'm duty-cyclying and I make a call to SplitControl.stop what will
>  happen? Will the radio be turned on and a SplitControl.stopDone
>  signaled?
>
>  If I'm calling LowPowerListening.setLocalSleepInterval with a value  
> of
>  zero what will happen? The interface comments in the interface says  
> that
>  the radio will always on but will I get a signal what let's me know  
> when
>  the radio reach that state? Will it be startDone or stopDone? Which  
> one?

Ah! Now this makes a lot more sense. Yes, this is kind of weird. I'll  
read through the code to try to get a handle on what's going on.

Phil