Do you want to learn about electronics ? I can give you some guidance...

I'm just a very curious hobbyists on how things work..

When LCD boot up, it should show a full bar on all the lines, you use the preset/trimpot on pin3 to adjust the contrast until you can see the BLACK bars.

Make sure all the Ground are connected.

LCD Smartie settings for LPT :-
Display Plugins is HD44780
Startup parameter = $E880

You need a software to make yr parallel port accessable on Win7. It is called port95nt.

For testing/running, try to use Power Adapter ( 5V ) with the correct current ratings... if you have multimeter, pls test the output voltage first...

You need to read the datasheet ( search google or seller ) and see the specs for MAX voltage and current requirements..

Using battery is not consistence as voltage will drop over time/usage...

I cut an extra USB cable and draw the power from USB ( red wire is +5V, black cable is Ground ) directly from the PC USB port...

Draw power from the Molex connector from PC Power Supply , Red is +5V, Black is Ground... dun use Yellow as they are +12V !!!

Another idea is find those extra Nokia/Ericson Mobile charger, some of them are small and rated at 5V.. just nice for this..


Good luck!!!!

No, it is NOT normal.. but you mention if voltage is 6V, then it shows all even brightness...

If power is sufficient, then it should NOT show uneven lines... use the trimpot connected to pin 3 to adjust until all show the darkness evenly..

You might need current limiting resistor on pin 15 & 16 bcos current from the molex is quite high... (it might work but it would reduce the life of the LCD )

Pic is here :-
Like this : http://arduino-for-beginners.blogspot.com/...les-part-1.html

Potentiometer or trimpot have 3 pins.. ( voltage divider )

Connect pin 1 to 5V
Connect pin 2 to pin 3 of LCD
Connect pin 3 to ground

Adjust the pot until you get all BLACK bar...

Yes, it should be WHITE for yr case...

I've a 4x20 LCD Black on Green, YES, it should be line 1 & 3 lit up full bar ...

I use a voltmeter to measure pin 3, the voltage is very small, in mV, so if you want full bar, just ground it for 0V.. and skip the trimpot... like the website you mentioned.

All these character based LCD are using the HD44780 protocol... can be different sizes, 16x2 20x4 or 40x2... all the same way of driving it..

Pin 15 & 16 are for the backlight, connect 15 to Ground and 16 to 5V..

*** Some of these LCD, the viewing angle is small, it will look full brightness (or darkness) at direct angle and looks dimmer at different angle..

Usually...on the datasheet, they are called Cathode(K) & Anode(A) (similar to a LED) but I've one LCD with the K & A reversed.

If one way did not work, just swap it around..

So did you managed to get the LCD working for LCDSmartie software yet ?

My case when I first constructed the Parallel port version, I had some grounding issues, so I need to trace all the cables...

Post some pics of your circuits with the LCD

Yes, Vmware surely works cos I did mine on WinXP on a Mac via Vmware Fusion...

For acrylic case look for lun1986 ..

Sometimes, if we manage to fixed the issue , you will learn more about how it works!!! Or else we just blindly follow the HOWTO without knowing what is going on..

I m researching to do "static LCD" with the lowest possible cost using DIY Arduino microcontroller + LCD only.. stay tuned...

I'm just posting a DIY solution to add LCD to yr desktop, not really selling it cos it is more fun to do it DIY style and you can customise it anyway you like it..

I think I've posted the parts and estimated cost in the beginning few posts...

You would need some basic soldering skills and can blindly follow the instructions without knowing what is going on..

I got PM that fellow.. but "no sound no breath" at all..

Do PM me if you hv any questions on the LCD projects..

Do not be turn off or scare of the electronic circuits, I myself is not an electronic person, just a curious hobbyists..

Can just "follow blindly" the connection, e.g. connect pin 1 here to pin 3 there... that all..


Two ways to obtain this, if you are a DIY person, than can do it cheaply by buying parts and assemble it yrself and that where the fun is...

If you just want the LCD to work like plug and play, then just buy the finished LCD panels with USB ( more expensive... )


Everything else is software/driver driven...

Hi Eric, nice to see that u r carrying the USB LCD product.. sometimes ppl just want the LCD at their desktop without the hassle of soldering, programming or finding a case... only very few ppl are interested in DIY / Modding stuff

I'll add yr WTS link to the first page...

Not need,ed the microcontroller (Atmega328) will read the values from the sensors and display it to the LCD screen without needing any PC at all.. it is a standalone system...