I2C LED 16x2 support
Started by cris bar




4 posts in this topic
hansehv

168 posts 17 threads Joined: Dec 2020
17-08-21, 00:11 -
#2
(16-08-21, 19:56)cris bar Wrote: I have change configuration.txt to 
USE_I2C_LCD = TRUE
I2C_LCD_ADDR=0x27     
I2C_LCD_PORT=1 ---> not sure about this number...


Also changed in file modules/I2C_lCD.py the adress to 0x27 (it was 0x3f)

The wiring from I2C to RPI is:
GPIO2 = Data
GPIO3 = Clock
PIN 4 = VCC
PIN 6 = GND


IM USING Linux Samplerbox 4.14.30-v7+
Hi Cris,

Configuration looks OK, port number is usually 1 - but hardware may differ.
The I2C_LCD.py didn't need your change, as some statements further this 0x3F default is overridden by the value entered in the configuration.txt.
Wiring looks OK as well (but read on..) and you're obviously working with the correct image.

So, all seems OK but it doesn't work. Hmm. I understand the frustration.

Being curious I looked around and stumbled on this, containing remark "I belive your PCF8574 board is a Chinese version which has the wires swapped on the board", which actually helped in this particular case.
However this is for Arduino and I couldn't really figure out WHAT wires have been swapped = how to cure this for PI.

Though not a solution, I hope above helps a bit.
Regards, Hans


Messages In This Thread
I2C LED 16x2 support - by cris bar - 16-08-21, 19:56
RE: I2C LED 16x2 support - by hansehv - 17-08-21, 00:11
RE: I2C LED 16x2 support - by hansehv - 17-08-21, 11:59
RE: I2C LED 16x2 support - by cris bar - 17-08-21, 13:21
RE: I2C LED 16x2 support - by hansehv - 17-08-21, 23:12