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Stellaris Launchpad and timers


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Hi Guys,
Another learning experience for me. I'm toying with the idea of implementing timers into my project which uses the STELLARIS launchpad LM4F.
I've never used timers before so the questions are going to be pretty dumb.
I think due to the choices of pins I have used, I may not be able to do it.
I have 8 ports set to trigger in a sequence. The ports I am using are as per below and I suspect I may not be able to use timers due to using ports PA4 and PE1.
I got the info from page 665-666 in http://www.datasheets.pl/integrated_circuits/L/LM/LM4F120H5QR.pdf
 
Flash #       Port       Pin Name               General-Purpose Timers Signals (64LQFP)
==========================================================
1                PF4     T2CCP0               16/32-Bit Timer 2 Capture/Compare/PWM 0.
2                PA4     ?                           NIL ?
3                PD0     WT2CCP0           32/64-BitWide Timer 2 Capture/Compare/PWM 0.
4                PD2     WT3CCP0           32/64-BitWide Timer 3 Capture/Compare/PWM 0.
5                PE1     ?                           NIL ?
6                PD6     WT5CCP0           32/64-BitWide Timer 5 Capture/Compare/PWM 0.
7                PC6     WT1CCP0           32/64-BitWide Timer 1 Capture/Compare/PWM 0.
8                PC4     WT0CCP0           32/64-BitWide Timer 0 Capture/Compare/PWM 0.

Am I right in assuming I wont be able to use a timer on PA4 or PE1 ?

And secondly, if I can get timers to trigger those 8 ports would they be able to trigger independently of other running code and not screw with this Fast Analog Read routine at the same time.
http://forum.43oh.com/topic/7153-stellaris-fast-analog-reads/?p=65472
Would just like to know if it is possible and if so I'll see if I can get it happening.
 
Thanks
PTB

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Hi L.R.A

 

Here's a link to the project thread I am working on.

 

http://forum.43oh.com/topic/7346-stellaris-launchpad-camera-flash-timer-and-measurement-tool/?p=65887

 

I just added an update to help paint a better picture of what I am doing.

 

Basically it is a flash timer and flash measurement tool. Currently I can get it to fire a user defined sequence or I can get it to measure a photographic flash pulse. But I cant get it to do both at the same time. I am hoping timers will help me with that. My plan was have the main program handle the Analogread to array while the timers are popping off those ports as listed in post above.

 

The reason I want to run both those events at the same time is I wish to fire off a timed sequence of flashes and measure the resultant combined flash pulse of that sequence. The goal is to confirm the timed delay settings are correct and have aligned the flash pulses. Aligning the pulses will remove ghosting from the photographic images. This generally applies to mixing different types of flashes.

 

I could buy several flashes of the same type and set them exactly the same. But where would the fun be in that ;)

 

Thanks

 

PTB

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