B4R Question Wemos D1 R2 analog pin A0

[tzfpg]

i like to ask how to make wemos A0 pin output 3.3v?
like this code:

 dim a_pin As Pin
a_pin.Initialize(a_pin.A0,a_pin.MODE_OUTPUT)
a_pin.DigitalWrite(True)

my all digital pin already fully in used, now left A0.

 

[Peter Simpson]

I might be wrong here but I thought that that A0 was an Analog input pin with a maximum input voltage of 3.3V. You should look up the WeMos D1 mini specs on Google, your answer will be there in the datasheet/specification sheet for pin A0.

EDIT:
https://wiki.wemos.cc/products:d1:d1_mini#pin

 

[Cableguy]

Yeap, you need to use either a pwm or a digital I/O pin

 

[Peter Simpson]

Have you seen this tutorial?
You can use three digital pins on your D1 mini to control 8 outputs. The operating voltage of the shift register is between 2.0V to 6.0V. If you put 3.3V to the VCC pin, you will get 3.3V out of the 8 pins, if you put 5V into the VCC pin, you will get 5V out.

https://www.b4x.com/android/forum/t...8-relays-wemos-d1-mini-wifi-android-4g.80909/

If I was you I would use a shift register, but that's only if you do not fancy purchasing a NodeMcu which has more digital pins...

 

[tzfpg]

Have you seen this tutorial?
You can use three digital pins on your D1 mini to control 8 outputs. The operating voltage of the shift register is between 2.0V to 6.0V. If you put 3.3V to the VCC pin, you will get 3.3V out of the 8 pins, if you put 5V into the VCC pin, you will get 5V out.

https://www.b4x.com/android/forum/t...8-relays-wemos-d1-mini-wifi-android-4g.80909/

If I was you I would use a shift register, but that's only if you do not fancy purchasing a NodeMcu which has more digital pins...

sure i had try, but i no more three pin for use shift register, my wemos connect to 2 rfid, 1 real time clock and 1 external eeprom.

 

[Peter Simpson]

Well in that case you should use a 16 I/O expander IC like this one https://www.b4x.com/android/forum/t...575-16-bit-i-o-extension-shield-module.81544/

You can use either the PCF8575 in the link above or an MCP23017 to expand your WeMos D1 mini up to 16 I/O pins by using only 2 of your original I/O pins on your WeMos D1 mini(D1 and D2). Both the IC's are controlled through I²C Bus communications.

Or buy a NodeMcu...