NodeMCU Projects: Difference between revisions

= I2C LCD =

https://forum.micropython.org/viewtopic.php?f=16&t=2858

https://forum.micropython.org/viewtopic.php?f=16&t=2858&start=30

https://github.com/dhylands/python_lcd/tree/master/lcd

esp8266_i2c_lcd.py

lcd_api.py

D1 SCL ------------ SCL

D2 SDA ------------ SDA

GND --------------- GND

5V ---------------- VCC

There are two versions of this device - the difference is the controller IC.

If you have the PCF8574T. the default I2C bus address is 0x27.

If you have the PCF8574AT the default I2C bus address is 0x3F.

An i2c.scan() should reveal which address to use

lcd=I2cLcd(i2c, 0x27, 2, 16)

lcd=I2cLcd(i2c, 39, 2, 16)

<syntaxhighlight lang="python">

>>> from machine import I2C

>>> i2c = I2C(scl=Pin(5), sda=Pin(4), freq=400000)

>>> print(i2c.scan())

>>> print(i2c.scan())

[63]

>>> lcd=I2cLcd(i2c, 63, 2, 16)

</syntaxhighlight>