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Wemos - GPIO Expansion possible?

PostPosted: Tue Sep 25, 2018 9:27 am
by Surfer2010
Hi,

is this setting possible? (GND, 3V and 5V cable are not drawn, so it looks simple).
HiLetgo CD74HC4067 (= multiplexer)
HC-SR04 (= ultrasonic sensor)

Image

I have those two questions:

1.) possible to use this multiplexer to expand the GPIOs at the Wemos D1 mini AND use the second multiplexer (same type) for analog multiplexing (for analog sensors)

2.) are the pins i'm using possible? I know that GPIO 2 (=D4) is activeLOW (as far as i know?) ... so can i use it like shown?

GPIO 12, 13, 14, 0 (= D6, D7, D5, D3) are regular and usable in all ways ... ?!

Thanks for your support!!!

(TX, RX and GPIO16 (=D0 --> deep Sleep connect to RST) and GPIO15 (=D8) are usable only with some additional pulldown/up resistors that's why i want to use the multiplexor

Re: Wemos - GPIO Expansion possible?

PostPosted: Tue Sep 25, 2018 10:43 am
by rudy
Your image does not appear in the post.

The A/D converter on the ESP8266 does not work very good. If you need more inputs then consider something like a ADS1115 Module.

For digital I/O have a look at PCF8575 , PCF8574 modules, or MCP23017 modules.

Re: Wemos - GPIO Expansion possible?

PostPosted: Tue Sep 25, 2018 10:53 am
by Surfer2010
rudy wrote:Your image does not appear in the post.

The A/D converter on the ESP8266 does not work very good. If you need more inputs then consider something like a ADS1115 Module.

For digital I/O have a look at PCF8575 , PCF8574 modules, or MCP23017 modules.


Does it show now?

https://picload.org/view/dcggaiwl/schal ... 3.png.html
Image

Re: Wemos - GPIO Expansion possible?

PostPosted: Tue Sep 25, 2018 10:54 am
by Surfer2010