ESP8266 Community Forum

- Sat Jan 02, 2016 11:56 pm #37752 There are certain pins that should not be pulled low on boot. I don't have a list of these pins. Possibly some one in the general area of the main forum would know the answer. I would be interested in this also so the information can be captured and published.

Serial terminal in the chrome browser see https://serialTerminal.com

http://esp8266basic.com
A BASIC interpreter for your ESP

Working now on Autodrop3d. A 3d printer with automatic part ejection system. https://autodrop3d.com

- Sun Jan 03, 2016 12:15 am #37753 Well from what I can find don't quite this as the gospel ...

I2C uses a single SDA line and the SCL line.

It is just a guess as to why they use GPIO 9 and GPIO 10 with LUA firmware.

And that guess is that there is 3 SDA pins so they use two of them knowing that they only need one of them for I2C communications.

Interesting bit of info don't quote it as gospel but indeed if this is the case I see no reason why basic could not do the same personally. Nothing like having a couple of extra GPIO pins on the Basic Wifi Dev Board or the NodeMCU for that matter.

Hrmmm maybe I should post it in the spice girls section ...

Helpful? Donate To help support Mike http://www.esp8266basic.com click the donate button lets keep this project going and hope we can get the ESP32 in the mix. BEGINNERS GUIDE HERE http://www.esp8266.com/viewtopic.php?f=40&t=6732

Where I buy my ESP8266 boards from... (Banggood)

- Sun Jan 03, 2016 1:03 pm #37789

More info to add to the research

Helpful? Donate To help support Mike http://www.esp8266basic.com click the donate button lets keep this project going and hope we can get the ESP32 in the mix. BEGINNERS GUIDE HERE http://www.esp8266.com/viewtopic.php?f=40&t=6732

Where I buy my ESP8266 boards from... (Banggood)

- Sun Jan 03, 2016 1:34 pm #37792 When your grid mentioned "N" for output on GPIO2 and GPIO0, what do you mean ?
Because they can be used as output, but with cares : we can attached LEDs on them, but not in Source mode, only in Sink mode to avoid false pulldown.
Personally, I used them for I2C bus, since the bus requires pullups and startup mode too, I2C bus becomes outputs only during LOW using open-drain mode.