Problem with connecting a MCP23017 with arduino Uno

Projects General Guidance
21

Hi,
Great mate, good to hear.
Hope you have success with the rest of your project.

Tom.. :grinning: :+1: :coffee: :australia:

22

hi,
@TomGeorge here's what I have in the oscilloscope as an output signal the output 0 on the 23017.

IMG3
IMG33260×2446 1.56 MB

Maissa.

23

Hi,
Does it go up and down with the LED on the UNO?

Tom... :grinning: :+1::coffee: :australia:

24

HELLO,
yes actually when I remove the LEDs I get 5v in the oscilloscope .

Maissa.

25

Hi,
Are you using a current limit resistor with the LED, say 470R or 1K?
You can't use an LED without some form of current limit.

https://www.sparkfun.com/tutorials/219

Tom... :grinning: :+1: :coffee: :australia:

26

HI,
ok I got it, thank you for the link it explain a lot. I should add resistors to the LEDs.
Maissa.

27

This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.