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Topic: ESP-13 + WS2812 - Can't find data pin (Read 350 times) previous topic - next topic

sejanus

Hi All,

I'm trying to hook up an ESP-13 Wifi module to a string of WAS2812 LED's and I'm having a bit of trouble getting it all working, here's the tutorial I'm trying to follow.

Had to modify the NeoPixelBus constructor line because the tutorial code was a little out of date but apart from that it all seems to work because I can load the webpage, but I can't seem to find the right pin for Data so I can get it to change colours using the web interface.

I'm actually not sure if I've even set the output pin up correctly so any input would be much appreciated - code attached :)





ieee488

It seems from the code that the LED is on pin 13.

sejanus

That's what I thought as well, but it doesn't seem to be the case - either that or I'm hooking it all up wrong. I've attached a diagram of how it's all hooked up, the Nano is in there as a serial debugger so I know what's going on but it will eventually be removed and the ESP powered by the external 5v circuit.

I'm also wondering if it's got anything to do with the modified NeoPixelBus constructor line, the original line referenced pin 4 as per below but using this constructor returned an error because it didn't use a feature list. 
Code: [Select]
NeoPixelBus strip = NeoPixelBus(pixelCount, 4, NEO_GRB);

The new constructor line I'm using doesn't reference any pin, wondering if this might have something to do with it but from what I've read you can't tell the ESP which GPIO pin to use, it'll ignore it if you do...
Code: [Select]
NeoPixelBus<NeoGrbFeature, Neo800KbpsMethod> strip(pixelCount);

Wawa

#3
May 30, 2017, 03:03 am Last Edit: May 30, 2017, 03:13 am by Wawa
Confused.
Are you just using the shield, or is it plugged onto an Arduino.

Are you sure the ESP is connected to any of the analogue or digital pins.
I don't see any tracks from the ESP going to any pins.
Datasheet is confusing. A table lists that the only connections are to the TX,RX pins.
Leo..

ieee488

Confused.
Are you just using the shield, or is it plugged onto e.g. an Uno.

The ESP on that shield seems only connected to the TX,RX pins.
Leo..

It isn't plugged into an Uno.

I will leave it to the OP to explain what he thought he was doing exactly.

sejanus

Confused.
Are you just using the shield, or is it plugged onto e.g. an Uno.

The ESP on that shield seems only connected to the TX,RX pins.
Leo..

To try and clarify further, I'm planning on using the shield stand-alone, the Nano pictured in the diagram is just there so I can view the debug output and make sure the web server was responding to input.


Wawa

That shield seems to be designed as serial<>WiFi bridge only.
No connections to the ESP I/O apart from TX,RX. And supply/reset etc.

You have to solder a wire to the relevant I/O pin(s) of the ESP if you want to use it stand-alone.
Leo..

sejanus

I'll have to see what documentation I can dig up but I was under the impression that this thing had it's own GPIO's rather than just being a pass-through for the GPIO or whatever it's connected to.

So you're saying those 2 groups of pins marked D + G (in my diagram I'm using D and G from pin #13) aren't connected to anything?

Wawa

#8
May 31, 2017, 06:38 am Last Edit: May 31, 2017, 06:51 am by Wawa
So you're saying those 2 groups of pins marked D + G (in my diagram I'm using D and G from pin #13) aren't connected to anything?
Correct for pin13, but ground is most likely connected (measure it to be sure).

As said, just solder the data wire to the ESP I/O pin of your choice, and it will probably work.
A pin protection resistor (~330ohm) inline with the data pin is recommended.
Leo..

Edit:
Just saw a printed separation line on the board.
All pins above the line are Arduino, and pins below are ESP.
Not sure about the numbers (I/O pins?), but these pins could connect directly to the ESP.

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