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1. 

   drinkdhmo
   Member

   I found an entry in the documentation for a function called pulseIn(). From the description there, it seems this is the function that will fulfill my needs to read a servo PWM signal from an RC receiver. However, when I try to compile, it fails with the following error:

   error: 'pulsein' was not declared in this scope

   Here is a snippet from my code:

   pinMode(ELEVATOR_PIN, INPUT);
   elevator = pulseIn(ELEVATOR_PIN, HIGH);

   Is there a library I need to #include? Is the function not yet implemented?

   Note: I am using the command line toolchain.

   Posted 3 years ago #
2. 

   StephenFromNYC
   Moderator

   Hello-

   According to the "Maple Language Reference" page (checked Feb 2012):

   http://leaflabs.com/docs/language.html

   pulseIn() is described as TODO.

   If you make any progress developing the code please contribute it to the project!

   Stephen from NYC (full disclosure: I am not a member of the LeafLabs staff)

   Posted 3 years ago #
3. 

   crenn
   Moderator

   It is possible to read in PWM signals a few different ways. The simplest way is to use external interrupts. If you want to use input capture in the timers, than the microcontroller manual is the way to go, although there is a mode in the timers that uses Channels 1 and 2 of the timer and means that the period and 'high time' as simple as reading a register.

   I've done this before to decode a ORed signal from 6 channels of an RC receiver. This is the code I used for that: http://www.crennsmind.com/Code/Maple/RCTXRX/RCTXRX.txt

   And if you need it, here is the EXTI code for individual pins: http://www.crennsmind.com/Code/Maple/RCTXRX/RCTXRX_EXTI.txt

   Posted 3 years ago #

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