How is the toggling rate slower in C than in Python when using sysfs? That
seems strange to me.

On Mon, Aug 10, 2020 at 12:31 PM Mark A. Yoder <[email protected]>
wrote:

> Interesting...  Why go through all the trouble to set bits on a chip by
> chip basis, and then end up setting them in a loop?
>
> Here are the toggling standings.
> c via sysfs:       3kHz
> python via sysfs:  6KHz
> c via gpiod:      300KHz
>
> Now to get python via gpiod to work.
>
> --Mark
> On Monday, August 10, 2020 at 2:19:27 PM UTC-4 Dennis Bieber wrote:
>
>> On Mon, 10 Aug 2020 08:33:55 -0700 (PDT), in
>> gmane.comp.hardware.beagleboard.user "Mark A. Yoder"
>> <[email protected]> wrote:
>>
>> >Interesting.... I wrote a c version
>> ><
>> https://github.com/MarkAYoder/BeagleBoard-exercises/blob/master/gpiod/bulk.c>
>> and
>> >the pins are toggle *at the exact same time*. Now, how to get gpioset to
>> >work correctly.
>> >
>>
>> It doesn't seem to use the same/direct calls... I've tracked it down to
>> the function at line 661
>> https://git.kernel.org/pub/scm/libs/libgpiod/libgpiod.git/tree/lib/core.c
>> and macro definition at line 778
>>
>> https://git.kernel.org/pub/scm/libs/libgpiod/libgpiod.git/tree/include/gpiod.h
>> which seems to define a loop operation.
>>
>>
>> --
>> Dennis L Bieber
>>
>> --
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