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Adding an LCD display to Arduino projects can add real value but the cost of doing so can be significant. Not a financial cost - you can pick up 16 (characters) x 2 (rows) LCD for as little as £3.50. The cost is the pin count it can take to drive them. Using the built-in LiquidCrystal Display library it can take as many as 6 pins! That does not leave much for your sensors, motors and other components.

There are many projects that discuss using alternatives - such as a much more expensive Serial LCD (£10 up). Other projects discuss using two-wire interfaces, increasing the complexity of your code. The simplest way to drive the HD44780 style LCDs, in my opinion, is to use a 74HC595 shift register, taking the pin count down to 3.

In any case, connecting an LCD either using the 595 Shift Register or the more traditional way takes a lot of wiring which is not only a super mess (unless you use a ribbon cable I guess), it takes time.

This shield is simplifies this process - all that is required is power and three wires back to the Arduino - ie. connect the LCD in under 6 seconds!

Step 1: Required Components

This is an extremely easy board to make and should take you no more than 15 minutes to solder up and have running.

Component List
    1 x 74HC595 Shift Register
    1 x BC547 NPN (or MOFSET or similar NPN)
    1 x 10k Trimmer Potentiometer
    6 x Male headers (I used right angle connectors)
    16 x Female headers
    Strip/Vero-board 17 strips x 13 holes (I used 15 for cable support)
    Hookup wire
    Your soldering kit
<p>I finished it! This uses and ATTiny85 replacing the take offs for pins 7, 8,and 9 from the Arduino. I also used pins 3 and 4 from the ATTiny to run two flashing LEDs just to see how it work. This is running off a 4.5v battery pack using AAA batteries. I'm glad i got this done,it's a nice unit!</p>
<p>Hey, how did you get your display multiple lines like that? I'm a noob and I need help haha</p>
<p>Its a 4 line display. im not sure what you mean by the question?</p>
<p>Brilliant stuff Jim. Looks great.</p>
<p>I thought this would be easy, but of cause it never is. But that was completely due to my sloppy reading.</p><p>So I managed in the end to get it working like it should and I certainly will build more of the shields to display readings from my Arduino. This certainly enhances the possibilities like thermometer, thermostats, clocks, etc etc.</p><p>I really like it, so thanks a lot for sharing,</p>
I have this running great from an ATtiny85. It also has a TMP36 temp sensor to desplay the current temperature. LCD uses pins 0, 1, 2 and TMP36 uses pin 3.
Here is my version. Thanks, it was a fun project. <br><iframe frameborder="0" height="315" src="http://www.youtube.com/embed/qKhqDKkguL4" width="560"></iframe>
<p>Hi, please where did you buy this stripboard? It was online? I just found another version with independent holes, different of yours... Sorry my English, thanks!</p>
That is fantastic Matt. Really nice work.<br><br>Being in London, I feel those cold mornings too.<br><br>Thank-you for sharing.<br>R<br>
Hey thanks bitterOz. I gave your instructables page props in the description of the above video and in the prototype video http://www.youtube.com/watch?v=1ipJzppZvVk <br>Thanks again, It was a fun project. <br>Matt
I'm wanting to build your project Matt. Any chance you could post the modified code for the attiny85?
Hi. Here's a link I made for you. <br>http://pastebin.com/saZ3ect9 <br>It should contain the code. <br>The temp sensor I use is a TMP36 from Adafruit.com<br>I hope this helps.<br>Matt
Thanks! You should really do an instructable on this, or at the least, draw up a schematic for us noobs and post it in the description of your video.
<p>I did it, Thanks</p><p>although I had to change a couple of things to get it done, and had to do a LOT of reading to finally make it wok properly, but learned a lot of things in this 6 seconds process :). Still on the breadboard.</p><p>Also thanks to <em>Build_it_Bob</em>, followed his advice on his comment and changed the pins of the transistor to the following:</p><p>Pin C (collector) of the 2n2222 to +5 volts</p><p>Pin E (emitter) to pin 15 of the Display.</p><p>Display Pin 16 to ground.</p><p>595 Pin 6 (Q6) to 1 k resistor </p><p>Resistor to Pin B (Base) of 2n2222</p><p>As I found out there are versions of 2n2222 with either EBC or CBE pins. Mine was P2N2222A with EBC Pins</p><p>I had to adjust the trimmer as well.</p><p>After I finally managed to make it work, i realized that it would write only the first character of any words or sentences printed. I had to edit the LicuiqCrystal595.cpp file, and add &quot;return 1;&quot; after the &quot;send(value, HIGH)&quot;, like bellow</p><p>inline size_t LiquidCrystal595::write(uint8_t value) {</p><p> send(value, HIGH);</p><p> return 1;</p><p>}</p><p>The lcd.setLED2Pin(HIGH); (or LOW) worked very nice as well</p><p>Thank you!</p>
<p>i need ur help,</p>
<p>i dont know,whats happened to mine,allconnections are correct,but <strong>my lcd is showing only one charecter,</strong></p>
<p>Okay so I've tried to build this on a breadboard and I have deleted the original liquidcrystal library, but I still get black boxes on the first line of the lcd. I cannot get it to print anything... Any ideas?</p>
<p>Hello! The project presented here is not working as is presented here, <br>if you will follow this instructable. I had the same problem like you, <br>and it seems that &quot;copy-paste&quot; method on ALL pages that describe this <br>metod, have the same issues. The problem can be solved if you put data <br>pin (wich goes to the arduino) on shift register pin 14 and LCD no. 6 <br>pin on pin 15 of shift register. The rest is the same. Also, you can <br>remove the transistor from the circuit and put pin 16 of LCD to ground <br>(GND) and pin 15 of the LCD to + Vcc (trough a resistor about 1K if you <br>wish to reduce luminosity).</p>
<p>Finally resorted to removing the transistor as you suggested and works fine. Still have not been able to figure out why the Arduino LED of digital pin 13 stays lit though.</p>
<p>I was confused about why the LED for pin 13 stays lit too. As it turns out, the LED is not driven directly by the pin - there is a buffer / driver that monitors the voltage on the pin. Pin 13 is configured as an input if not used, and so the voltage on the pin floats high enough for the buffer to turn on the LED. Connect a 1k (or whatever you have) resistor from ground to pin 13, and the LED goes out. </p>
<p>That does make sense. Should try that. </p><p>Thank you</p>
<p>i can not get the librarys to work on my arduino at all dont know why </p>
<p>I made it. But my LCD would not show any text. Is it the potentiometer problem or something else as the the backlight also blinks sometimes. The lcd backlight is always ON but nothing else.</p>
<p>Made it without the NPN transistor</p>
<p>HI, firstly thank you for this instructable. I made it and literally burnt the midnight oil working till 2 AM and was frustrated that it didn't work. The following morning I found the flaw in a few minutes and now it works like a charm. There is a mistake I would like to point out in one of your diagrams though and I have attached the picture to show where the error is. Hope you would correct the original picture.</p><p>Two other question I have are</p><p>(a) why does the LED corresponding to pin 13 on the Arduino stay lit after displaying the message?</p><p>(b) How do I get the back light to come on?</p><p>Please advise.</p>
<p>can u please mail the library zip file to sangeeth123@gmail.com. i cant download from the link above</p>
<p>Hi sir, i already built the circuit according to the steps , load the program and use the library from new website, but suddenly the output is no display, and also the backlight turned-off when i am trying to reset the arduino board and never turn-on again.</p>
<p>I have every thing up and running very good now thanks all </p>
<p>You did not explained well at start therefore I had to start the whole soldering from the begining.</p>
<p>... read, read again ... start!</p><p>Enjoy!</p>
<p>OK now I was able to make it. But the code compiling is not successful. The library page has moved to somewhere else. Ahhhh. </p>
<p>I cant download the library, it says, that the page has been moved to somewhere else, but there is nothing about downloading the code</p>
<p>This should be fixed now AngeloP2. </p><p>This was caused by Google closing down their service. We found a new home with BitBucket now.</p>
<p>Thanks for writing up the article, I notice at the end you've got a Fritzing layout for the breadboard method - any chance you could send it to me? I'd like to integrate the shift register LCD into a project I'm doing and build a PCB via Fritzing, the original file would help make sure I don't get something wrong translating it across :)</p>
<p>Of course. Send me a private message and I'll mail it to you.</p>
<p>Hello I am having a very hard time getting all this to work with the shift register </p><p>i have the 74hc595 and an HD44780 but I cant get the library to work with my </p><p>arduino version 1.6.4 i keep getting error messages it says library not found ?</p><p>and i know it is installed </p>
<p>you could try and remove the existing LiquidCrystal library, quit the IDE and restart it. </p><p>Let me know if that works for you.</p>
<p>BUT I COULD NOT GET THE BACKLIGHT TO COME ON WITH AN NPN SO I USED A PNP WORKS GOOD</p>
<p>can you tell me why the transistor is even there?</p>
<p>The NPN is there so you can turn on/off the backlight of the LCD via code. If you do not wish to have this feature, you can bypass it. By default, the display is ON.</p>
<p>Hi!</p><p>First thank you, it is a great idea and so useful (i run out of pins :D)<br>However I have a problem. When I connect everything it worked. Then the second time on the LCD there is just some boxes in the first row, nothing in the second. The potmeter works fine, but its only effect, the boxes became brighter. No text, no hello world, no nothing. What could be the problem? </p><p>I checked the every connections, it should be good.</p>
<p>Hi. I have not seen this behavior before. Are you still experiencing the same issue? Perhaps put a delay(2000); in setup() to give the all the components a little time to settle.</p>
<p>Arduino: 1.6.4 (Windows 8.1), Board: &quot;Arduino Uno&quot;<br><br> fatal error: LiquidCrystal595.h: No such file or directory<br>compilation terminated.<br>Error compiling.<br><br> This report would have more information with<br> &quot;Show verbose output during compilation&quot;<br> enabled in File &gt; Preferences.</p><p>this is what I get when I try to run the code any ideas ?</p>
<p>HI electric1981.</p><p>Sounds like the library has not been installed correctly. Can you please check your library folder and make sure the LiquidCrystal595 folder is there and contains the LiquidCristal595.h file?</p>
<p>Forget this rubbish. The library doesn't work. Don't waste your time.</p>
<p>I LIKE YOUR INSTRUCTIONS THEY WORKED GREAT !</p>
<p>How crucial is transistor Q1 where the 595 pin 6 connected to the base of Q1 feeding the LED- (16) of the LCD? from what i can tell it only controls the backlight of LCD passing GND. could pin 6 be left disconnected?</p>
<p>I am a bit confused by the jumper that runs from the second row from the bottom between the sixth and seventh columns from right. It does not seem that this does anything since the seventh column is cut below and above this jumper. Am I miss reading something?</p><p>Thanks for the tut. Looks very good overall.</p>
<p>I am looking at using the lcd.noBacklight() and it is not recognized at compile time ?</p><p>liquidcrystal595 has no member named &quot;noBacklight&quot;</p><p>Any other way to turn the backlight off using the 595 library ?</p><p>I am very happy with the functionality of this display , thanks again for sharing.</p><p>Build_it_Bob </p>

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