Hi phil,
I just want to sample four channels. But to do it like you say: >acquire resource >sample 1 >sample 2 >sample 3 >sample 4 >sample 5 >sample 6 >release resource For each channel i need a seperate config (4 channels = 4 configs). So do i need one instance of the ADC interface and one of the resource interface, and reconfigure it during runtime to sample the different channels? Request() Configure(1) Sample1 Configure(2) Sample2 Etc.. Release() Or do i need 4 ADC instances and 4 resource instances? Or maybe 4 ADC instances and one resource instance? This is a bit confusing for me. Thank you, O.Chougna granted -----Original Message----- From: Philip Levis [mailto:[EMAIL PROTECTED] Sent: vrijdag 15 juni 2007 20:27 To: Oussama Chougna Cc: 'Nicolas Esteves'; [email protected] Subject: Re: [Tinyos-help] Multichannel Adc sampling and DMA On Jun 15, 2007, at 1:46 AM, Oussama Chougna wrote: > Hi Phil, > > > Are you sure about this: > >> Timer.fired() { >> call Channe1One.read(); >> call ChannelTwo.read(); >> call ChannelThree.read(); >> call ChannelFour.read(); >> call ChannelFive.read(); >> call ChannelSix.read(); >> } > > Is the first approach only possible with the HIL ADC component > ADCReadClientC? Because with the (msp430) HAL interfaces the client > should > do resource arbitration. (request() , configure() , getData(), > dataReady() , > release() ). So you cannot call getData() of each channel one after > the > other in the timer.fired() event? > Ah, then what you what to do is acquire resource sample 1 sample 2 sample 3 sample 4 sample 5 sample 6 release resource Basically, for maximum efficiency you don't want the lock (resource) to go idle. That's why enqueueing all the requests as I showed with the HIL is desirable. The lock won't be released until the sixth channel is read. > Which would you recommend for 100 Hz sampling? (HIL or HAL) You want to sample all 6 sensors at 100Hz? I'd say try using the HIL (it's simpler) and if it can't do the job use the HAL. The one thing to be careful of is that if you let the ADC go idle long enough, it might power down the voltage reference, which has a 17ms warmup time. Phil _______________________________________________ Tinyos-help mailing list [email protected] https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
