Read GPIO problem
#11
(08-07-2017, 07:21 AM)MarkHaysHarris777 Wrote: Note:  I do understand 'what' everyone believes export "should" accomplish, and I certainly also believe that it should be possible to guarantee the default operation of an exported pad;  however, my personal 'reality' is that it is more important to help users understand the complete operation rather than arguing over what 'should' be happening.  At the end of the day, do you want the pad to work or not ??  That's the simple question you need to answer for yourself.

Um, don't you mean you understand what export DOES on the board that people are most familiar with this funtionality? Because on the raspberry pi, there is no need to set the direction, because the initial sysfs values are correct!! Tongue When you export a pin, and then do a 'cat /sys/kernel/debug/gpio' on the rPi, the values you see are actually representational of the pin state, not false (i.e. gpio-4 sysfs in lo).

However, when you move to other boards, such as the Orange Pi Zero, you are out of luck... they are left floating just like with the pine64. Yes, it is nice to have it working, but exceptionalism is not good either... because this means this is yet another thing that makes the RPi-2 bus not RPi-2 compatible. So at the end of the day, I would like to either make it do what everyone expects it to do, or if that is not possible, document it as a known issue, because it is not rPi behaviour. Anything else is just looking at it with rose-tinted glasses, and making excuses.
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Messages In This Thread
Read GPIO problem - by shworker - 02-21-2017, 04:00 AM
RE: Read GPIO problem - by Techsensei - 02-21-2017, 06:41 AM
RE: Read GPIO problem - by shworker - 02-21-2017, 08:58 AM
RE: Read GPIO problem - by MarkHaysHarris777 - 02-22-2017, 04:23 AM
RE: Read GPIO problem - by aromring - 08-05-2017, 09:59 PM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-05-2017, 10:24 PM
RE: Read GPIO problem - by pfeerick - 08-06-2017, 01:33 AM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-06-2017, 10:38 AM
RE: Read GPIO problem - by pfeerick - 08-07-2017, 12:11 AM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-07-2017, 07:21 AM
RE: Read GPIO problem - by pfeerick - 08-07-2017, 07:21 PM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-07-2017, 11:10 PM
RE: Read GPIO problem - by pfeerick - 08-08-2017, 06:20 PM
RE: Read GPIO problem - by MarkHaysHarris777 - 08-15-2017, 02:24 AM
RE: Read GPIO problem - by martinayotte - 08-17-2017, 01:21 PM

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