LaFonera Hardware LCD Screen

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[edit] LCD screen for LaFonera


La Fonera is a really nice toy. I have already deacivated serial console because of playing with IR receiver. So why not playing with serial 128*128 LCD ?

The LCD 128*128 screen module come from 4D Systems and sell by Dontronics. My LCD module is not in product any more. The new OLED model is more rich and include à micro SD reader for storing images and animations. The uLCD model can only display simple stuff (line, cercle, text) and pixel after pixel images.

That’s not really important. What we can do with old uLCD can be done with OLED model. Connecting uLCD is quite simple. The LCD module is powered by +5Volts get from La Fonera, serial interfacing is +3.3/0V (like the serial port of the router).

Ok ! Nice ! All i have to do is to connect uLCD with router. Right ? NO !

The first thing we need to do before driving uLCD is to ask the the module to autodetect serial speed. This is done by sending “U” to the module before anything else. But RedBoot talk a lot at boot time and send characters to uLCD module. We can change RedBoot but it’s not so easy. And we need to have control over the router if something goes wrong. Don’t touch at RedBoot.

The right way is to power up the uLCD module avec complete boot process. All GPIO lines at the back of the router are in use for my i2c bus but i have the Wan Led. We need to remove led and transistor and use this GPIO line (2) with BC547 transistor :



uLCD module can by driven with a simple C program. It’s a very basic code that can control uLCD module and send image to the display (slowly).

Here is the stuff :

sources tarball for OpenWrt (mirror)

binary IPKG package for Kamikaze 7.09 (mirror)

I’m not sure you can compile from source with your OpenWrt BuildRoot. Build/InstallDev rules from libGD Makefile are… strange.


Maowwwwwwww !

You also need the proc_gpio kernel module:

proc_gpio.ko (mirror)

proc_gpio.tar.gz (mirror)

So you can power up the module like this :

insmod  proc_gpio
echo 1 > /proc/gpio/2_dir
echo 1 > /proc/gpio/2_out

[edit] Refrences

this page was made by wildblue!