Does ESP8266 support internal pull-up resistors?
Posted:
Mon Jul 27, 2015 4:34 amby helpme
Does ESP8266 support internal pull-up resistors so that one need not connect external pull-up resistors when using i2c devices?
Re: Does ESP8266 support internal pull-up resistors?
Posted:
Mon Jul 27, 2015 8:14 amby kolban
Apparently yes. See section 3.1.1 of this document.
http://bbs.espressif.com/download/file.php?id=520
Re: Does ESP8266 support internal pull-up resistors?
Posted:
Mon Jul 27, 2015 8:21 amby martinayotte
The specs don't mentioned what are the values of those internal pull-ups.
In other products, they are often "weak" pullups, something between 47K to 100K, enough for normal GPIOs, but for an I2C bus, this is not enough. So, it is better to have external ones around 4K7.