Request for GPIO Examples

[Worth Burruss]

On 23 Mar 2016 at 0:57, punit vara wrote:

> Hi Worth Burruss,
> 
> This year I proposed a plan (https://goo.gl/cGCXbS) to develop Beagle
> bone black BSP which includes PWM drivers as well as I2C driver. Could
> you please suggest me testing methods to test PWM on BBB ?
> 
> Regards,
> Punit
> 

Punit,

I will preface this with my solutions tend to be overly complex and I do not know specifically 
what is available to use to test with in the BBB.  So this may not be what you are looking for.  
It also depends on the frequency of your PWM signals.

When I think of test on hardware, I want to know it is working the way I think it is working 
(proving correctness).  For PWM, this means the duty cycle is correct.  I would be using 
another hardware counter timer to measure the High time followed by the Low time and doing 
the math to prove that the times are correct for the programmed duty cycle.

As an alternate, with appropriate selection of PWM frequency and software timers, you can 
do the High and low counting using the timers.

As for me, I would find it hard to see the change in an LED's intensity except in a crude 
fashion, so would not meet my personal goal of proving correctness.   But you may be 
thinking of ON and OFF times in seconds, In which case an LED and maybe a stop watch 
would be appropriate.

Hopefully this gives you some ideas.

Thank you,

Worth Burruss