LCD i2c Problems

Running Volumio on Raspberry Pi B with IQ Audio Pi Dac. I’ve been able to successfully connect an hd44780 compatible LCD screen and get track info output via mpdlcd. Since the IQ Audio Dac exposes i2c (SDA, SCL) pins I’d much rather use these for LCD output. I purchased an LCD i2c backpack from Adafruit and successfully tested it by hooking it up to an Arduino.

I’ve followed all the steps to install necessary software and ran i2cdetect…display was detected at port 0x20. I edited LCDd.conf to reflect “i2c” connection type as well as “/dev/i2c-1” as the device. Unfortunately I get no output to the LCD except a row of solid blocks. Not sure what I’m missing or doing wrong. Any help would be appreciated.

I think the Adafruit i2c backback uses the mcp23008 chip.


Did you check your Connectiontype, Device and Port in LCDd.conf ?

[hd44780] ConnectionType=i2c Device=/dev/i2c-1 Port=0x20 ..........

Did you try the code from adafruit to test your LCD?


I’ve solve a similar problem by using another driver for hd44780 . I don’t remember where I found it. I’m not at home I’ll have a look tonight if you still need it.

In fact the wrong driver doesn’t display a bloc line but some ascii caracters.
Or other way : lcdproc does not start.
Have you try to restart manually ? what message erro

As stated in my original post I’ve verified all the correct settings in LCDd.conf. I haven’t tried code from Adafruit yet but will give that a shot. I’ve also noticed that a majority of people are using the PCF8574 i2c expander rather than the mcp23008 which is what the Adafruit board uses. Although I’d much rather figure this out, I may also consider ordering the PCF8574.

As far as restarting lcdproc, I’ve rebooted, restarted everything multiple times. Still not giving up yet.

mine is that one : … y_ce_img_y it is rather cheap…
it is detected at adress 0x27 and works … used here : second-rpi-volumio-project-t2680.html :wink:

I received yesterday my Pi-DAC+ and attached to the Raspy.
I also bought a 2004 with i2c interface. Could you share some tips or links about wiring the three components?
Also I know that I need a level converter 3.3 to 5 volts.

For I2C you will need 4 pins only - 5V, GND, SDA0,SCL0. Please proceed to link below to find teh GPIO layout. There are a number of pins for Pi Amp on your DAC and you can utilize them for your LCD. I suppose that Pi DAC has the same GPIO layout with RPi and other sound gizmos like Hifiberrry. … sion-1.png