Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Pullup resistors on I2C, why? #19

Open
atrent opened this issue Jun 6, 2019 · 2 comments
Open

Pullup resistors on I2C, why? #19

atrent opened this issue Jun 6, 2019 · 2 comments

Comments

@atrent
Copy link

atrent commented Jun 6, 2019

Hi, is there a motive for R1 and R2 (pullup resistors for SDA and SCL)?
I'd like to use Wemos pins D1 and D2 for a SoftwareSerial...
Thanks

@pfeerick
Copy link

Because I2C needs pullups.

If you're not going to use I2C, don't put them on.

@atrent
Copy link
Author

atrent commented Jul 10, 2019

thanks for the reply (and sorry for the delay in my follow up)

I actually have an old version of the shield (see photo) and I've checked now that R1, R2 and the 24AA... chip are NOT present, so the fact that I could not activate a SoftwareSerial on those pins is to be investigated more, my bad

2019-07-10 08 38 51

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants