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Re: GPIO Flicker

PostPosted: Fri Dec 12, 2014 4:25 pm
by hwiguna
Markus Gritsch wrote:Hi Hari,

since you are doing some bit banging in your shiftOut function you might be interested in this posting: viewtopic.php?f=24&t=832

Have fun,
Markus


Thanks for the great tip!

Re: GPIO Flicker

PostPosted: Sat Dec 13, 2014 4:02 pm
by hwiguna
hwiguna wrote:
hwiguna wrote:Alas, when I run a webserver on the ESP. The I/O flicker returns, and shift register stopped working :-(

This appears to have been error in my lua code. :oops:
I've since been able to get the ESP-03 drive a shift register AND respond to web requests.
Here is the code and more related videos here: viewtopic.php?f=19&t=845


Re: GPIO Flicker

PostPosted: Sun Dec 14, 2014 8:19 am
by Markus Gritsch
Hmm, I cannot confirm any GPIO flickering. Here is what it looks like when switching from 0 to 1 when powering from a 3.3 V regulator:

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When powering from the 3.3 V of the FTDI adapter (which cannot provide enough current) I added a 470 uF capacitor. This is how it looks in this case:

NewFile1.png
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Not as good, but still ok.

Re: GPIO Flicker

PostPosted: Sun Dec 14, 2014 2:11 pm
by Markus Gritsch
Hi Hari,

from watching your YouTube videos, I think I know what's causing the problems in your circuit: You are using a 3.3 V regulator, but you have to add capacitors before and after the regulator to give it something to work with. Typically you would add 1 uF from the regulator input to ground and 1 uF from the regulator output to ground. Look into the regulators datasheet. It will contain some application circuit showing these caps.

Have fun,
Markus