ESP8266 Community Forum

- Fri May 05, 2017 9:07 pm #65630 I'm pretty sure that the pull up was for the RX line and not a required for TX. At least that was my experience.

It would be great if information like this were easily accessible. As you found, the information has been posted before. The problem is finding it. Using the right search terms to get you to the information you need.

- Fri May 05, 2017 9:24 pm #65631

I'm pretty sure that the pull up was for the RX line and not a required for TX. At least that was my experience.

It would be great if information like this were easily accessible. As you found, the information has been posted before. The problem is finding it. Using the right search terms to get you to the information you need.

No it was definitely the Tx, which was not intuitive - it's an output and you need to shut it up when it's not connected to a serial line or else it acts like a transmitting antenna and any serial data you are spitting out becomes interference.

I have seen people putting resistors in series on the Rx line to make them 5V tolerant, but not pull ups.

I've been searching looking for the original post - when I find it I'll tag it here, but I agree - I might even make this a topic so that it stands out more. These sort of design tips would be so useful if they were more visible

- Sat May 06, 2017 12:32 am #65636 Found it!

viewtopic.php?p=43646#p43646