My work on this ongoing LCD Arduino project has been continuing over the last couple of weeks, I just haven’t had the time to update appropriately.

So, I switched over my plan of attack from Processing to PHP. I figured this made sense for a couple reasons: first, I’m already very well-acquainted with PHP, I’ve written and hacked together a good amount of code in this language before and so I feel like I’ll spend a lot less time just figuring this out and more time actually doing; second, I don’t think I was really going to use Processing for its strengths, and instead, I was going to rely on its string functions, which pale in comparison to PHP.

I’ve made quite a lot of progress over the last week or so — all of which is detailed below. There are still some major problems I need to sort out, but for the most part things are about where I’d hoped them to be at this point.

First off, I had to spend some time getting the server up and PHP and running on my MacBook Pro again. I had set this up a while back, probably before I upgraded to Leopard (and having since upgraded to Snow Leopard), some things needed some manual attention. I wish I had saved the links, but the gist of it was that I needed to change the user.conf file.

I also started working with the PHP Serial class, which is awesome, there are a few versions out there, but the one I’m using came from Rizwan Kassim who made changes to the oft-circulated Rémy Sanchez version.

So, I tweaked the example script to spit out the text that would appear on my LCD screen in my browser window.

Here’s the script.

And the result.

Then I moved onto a looped script.

This worked fairly well.

The script … wrapping the $serial -> sendMessage($i) in a while statement.

My diagram for what exactly I want this to do…

The counting numbers script was a bit wonky for reasons I’m not entirely clear about. Basically it would count up to a certain number, but then clear the screen and print the rest of the numbers. That is, if I wanted it to write up to 11, it would split the number sequence somewhere near 6 or 7, and then show the rest on a freshly cleared screen. I’m not sure why this was happening, but I wondered if the script was just moving too slowly (or too quickly) for the Arduino to catch it all at once.

Then I spent a long time trying to figure out how to break up the text correctly. The thing is, I had hoped for this project to be able to take a text string and display it all at once on the LCD screen. However, the LCD screen and Arduino don’t know how to automatically display this as I might wish. There are some inherent difficulties in this — while PHP can find me letters or entire words and break them up accordingly, I’m not sure how to signal Arduino to tell the LCD to start a new line. You can see above, I had momentarily programmed the PHP script to display correctly in the browser, but it made me think that if I could just find the right catch character, I could get this to work as I imagined.

The other thing that you’ll notice is that the Arduino sketch as I had written it at the moment, wasn’t right in its placement of characters on the LCD.

As I understand it, these LCDs are meant to write to the 1st line, then the 3rd, then the 2nd, then the 4th.

In this case, I had the Arduino sketch printing out one letter at a time — and I realized I actually liked this effect (simple I know), but I think it helps to communicate some level of this thing actually receiving new data.

One of the many Arduino sketches I was trying to piece together from other tutorials, etc. At some point I think I was trying to use command characters that I saw on Serial LCD tutorials — my LCD is parallel, so I have to imagine this is a big reason why it wasn’t working.

So, back to the drawing board…

This time, I got it to work…

See the comma — it went to the 2nd line, like it was supposed to!

The string carried on, though it’s awkward with not being able to determine in PHP where the string should break for a new line and have that information sent on to Arduino.

Here’s a screenshot of the Arduino code I’d settled on. Those letter variables are a counter for each line, allowing me to have Arduino automatically wrap the entire string when it’s reached the end of each line properly so that the string continues onto the next line, rather than the 1-3, 2-4 thing I described above.

So the string continues.

And here’s the string completed. Really awkward line breaks in the string, as Arduino will print until its reached 20 characters on each line. You can see why I need to figure out how to translated information from something like wordwrap() in PHP to Arduino.

And again, here’s the code that finally made this work, all those counters…

The other part of this project that I started to work towards is the process through which I will receive text messages and put them into the system. Sending text messages from computers is easy, but receiving text messages in an email or something like that is much more difficult. However, I found

Problems that remain at the moment:

I’m still not sure why I need the Arduino Serial Monitor open for this to work. Unless it’s open, the PHP script won’t work and because it doesn’t work, it gets stuck with the Serial port open, it crashes the Arduino IDE and the LCD itself obviously has no output.

I still need to figure out how to signal a line break earlier than 20 characters when appropriate. I can get this information about a string and split it up in PHP, but I’m not sure how to pass that along to Arduino. I’m guessing using something like a case break type of loop would do it. iPiPi seems to provide the technology that I need, which is essentially a number that can receive text messages and automatically route them to an email. The service that I need is going to be fairly costly, given that I’d want a dedicated number or long code, but would be worth it to see this project work as I imagined it … that part of the project is a little while off anyways. But, I’m just happy that I found what I was looking for.

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Annotated bibliography for the last couple of weeks:

http://dorkbotpdx.org/blog/kmat/serial_lcd (serial –> LCD … this is making more sense now, using case breaks to look for specific characters to insert a function, such as starting a new line)

http://blog.datasingularity.com/?p=50 (control arduino through html)

http://stackoverflow.com/questions/899098/arduino-serial-reading (arduino serial reading)

http://www.ipipi.com/ContactUs.do (potential sms forwarding to email option)

http://www.ipipi.com/help/ipipi_in_out.htm (this is what I would need to receive messages, not as simple as a number, but maybe the best way to avoid having to get another phone number, I should also ask about a potential shortcode)

http://docs.upsidewireless.com/index.php?title=MO_HTTP (notes on how to bring sms messages into an application using HTTP POST)

http://www.upsidewireless.com/how_virtual_sms_works.htm (this is the kind of service I’ll need for this project … SMS messages forwarded to email or accessible through HTTP requests … with the possibility of getting a Windsor-based number AKA longcode)

http://www.mydarkmaterials.co.uk/2008/11/interfacing-php-with-the-arduino/ (this is an example of interfacing PHP Serial with Arduino, and I suspect old enough that many of the problems the author ran into aren’t there any longer … maybe it’s been silly of me to ignore PHP … I actually have a decent idea of what I’m doing there)

http://www.procata.com/blog/archives/2007/10/28/working-with-php-5-in-mac-os-x-105/ (helpful to get PHP running properly on 10.6)

http://opensourceprojects-torchris.blogspot.com/2009/09/arduino-pop3-email-checker.html (maybe or maybe not useful in some capacity, using arduino to check email)

http://www.arduino.cc/playground/Learning/SparkFunSerLCD (serial commands)

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?action=print;num=1192470251 (word wrapping in Arduino)

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1252901403/4 (word wrapping more)

I would like to thank the Canada Council for the Arts for their generous support.

I haven’t posted on this project for a little while, partially because of the preparation for the ongoing Save the City project, and partially because the little time that I’ve had to work on this has only resulted in small increments. So, I figured I would wait until I had some more significant updates to make to post, and here they are.

Basically, I’ve been working on a couple parts of the project. I’ve been updating a Max/MSP/Jitter project that BCL had previously used for our projection performances to try to automate some of the scaling of text depending on what the input is, while also continuing with the Arduino and LCD integration.

So first, some of the shots of the Max patch.

It’s a bit crude, but basically, the patch will ask for the number of letters per line and then scale the text size appropriately.

However, I couldn’t figure this out on my own. I made some notes on the relationship I was seeing, but I wasn’t sure how to translate that mathematically.

I figured the relationship was something like this.

So, I called my brother with a degree in engineering, and asked him for some help. He came through!

This is what he came up with initially: 625 * x^-1 … I adjusted it a bit to 925, as that number seemed to do better with more letters, which would more often be the case.

So, here’s the patch work, doing a good job at scaling 3 letters to the appropriate size to fill the majority of the window. The reason I’m continuing with playing with this Max patch is that it may provide an alternative to the Arduino+LCD combo if it doesn’t end up working the way I need it to.

So, after some frustration a little while ago, I picked up some new screens and everything is working as I had hoped. I’m still not sure why I was having troubles before with the contrast, and it’s frustrating that I couldn’t come to some resolution about it.

I had picked up a book on Processing and I’ve skimmed through it a couple of times in the past, but never when I actually had time to work in Processing on a project.

So, at first, I was just trying to figure out how to understand Arduino and Processing talking to one another. I ran some example patches and I didn’t get any warning flags when running the serial library in Processing, so I set out trying to test the actual communication.

Here’s another example, I can’t quite remember what this resulted in specifically, and it may have been that I was just trying to run another basic test to ensure something was working as anticipated.

Next, Processing listed the available serial ports, using the first one in the array worked perfectly.

The result – hollar! – the first thing I sent to Arduino from Processing. It finally made sense to me: Arduino needed a sketch that will listen (or technically read) from the Serial port.

And here’s the Arduino patch that did that work!

Shortly thereafter though, upon trying to backtrack, simplify and just have the process start without having the Arduino client open, something wasn’t working. I couldn’t figure it out, so I tried to think back to how I had set it up in the first place. Conceptually, I had difficulty understanding how this serial port thing worked. Something finally clicked. Processing needs to send messages through the Serial port.  Somehow I wasn’t cluing in to envision it as an actual port that data would pass through. I’m not sure why I didn’t pick up on understanding the relationship between Arduino and the serial port for stuff like this earlier. Looking at the examples that used Python may have confused me I think, since I don’t know that language. Looking at them now though, I understand better how it all works.

Arduino just needs to listen for something coming over the serial port and then ask the LCD to print that incoming message.

It also helped to finally test with the serial monitor from Arduino environment, which helped to illustrate immediately what was going on. I think I understood the basics of serial port communication (as in, a message can be sent over this), but I wasn’t cluing in that Arduino had to be setup to listen for those messages, which may have led to some of my confusion.

However, it seems as though I need to open up the serial monitor and send a message to Arduino before it will hear anything from Processing. I wonder why — I assume I’m not initializing it properly?

Upon further reading, my other thought is that the Serial port isn’t available to Processing, possibly it’s in use by something else, thereby preventing Processing from accessing it? The strange part, though, is that once I open the Serial Monitor in the Arduino environment / client, Processing can send messages without any problem. I’ll have to look into this some more.

And, once again, the Arduino patch that makes this all work.

At any rate, things are moving along nicely. I’m doing some replicating of other people’s projects to familiarize myself with how to integrate an Arduino and LCD screen into something a bit more automated.

Next on the list, start having Processing cycling through text files. There’s a lot of examples of this using Python, but I’m going to look into Processing instead.

Annotated bibliography for the last couple of weeks:

http://www.ladyada.net/make/pumpkin/pumpkin.html (great idea for introducing a distributed urban surface sound project)

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?action=print;num=1181079252 (solar-powered Arduino help)

http://www.adafruit.com/index.php?main_page=product_info&cPath=35&products_id=172 (range finder)

http://www.adafruit.com/index.php?main_page=product_info&cPath=37&products_id=198 (the LCD screens I got)

http://clete2.com/2009/11/control-lcd-text-over-web-interface-arduino/ (controlling LCD over web)

http://www.arduino.cc/playground/Interfacing/Processing (Interfacing Processing and Arduino)

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1255733236 (Process + Serial + LCD to display Tweets)

http://itp.nyu.edu/physcomp/Labs/SerialOut (some tutorials on physical computing)

http://drewish.com/content/2009/06/simple_arduino_serial_communications (simple serial communications)

http://www.akeric.com/blog/?p=1015 (arduino / processing / python)

I would like to thank the Canada Council for the Arts for their generous support.

I spent the better part of the day on Saturday doing some more basic research into connecting an Arduino and LCD for this ongoing project. For the most part, it’s pretty basic and following the wiring diagrams and tutorials online is fine.

I ran into a problem with getting text on two lines, which I’ll detail below. Next on the to do list is to order a different LCD, maybe a 4×20 display and maybe something even smaller and then do some work on the text processing part of this whole thing.

Overall, it was a good start and I’m anxious for later this week when I’ll have a block of time to continue with the next steps in this early research.

First thing after pulling this stuff out again, I followed the wiring diagrams and I connected the data wires, leaving the power and ground until the end.

An initial sketch. Really, really basic “hello, world!” program. However, this was before I installed the newest version of Arduino, which is why that error came up.

Installing version 0017 helped and I finished connecting the LCD.

It’s not ideal, but quick and dirty. Also, it seems like there are better screens out there in terms of connections.

The arduino side of things.

I figured that it would be better to not be so tightly tethered to the Arduino, so I used the breadboard.

Trying to make connections a little cleaner.

My first program, working!

All the wires, still a mess, but I was just too anxious to get something on the screen.

BROKEN CITY LAB!

Then I worked on another program that would flash different texts.

This one switched between BCL and make things happen!

Here’s the code, trying also to change the position of the cursor, which didn’t work as anticipated because I didn’t initialize the screen with lcd.begin().

I switched the wiring around to try to figure out how to get text on two lines.

I also connected the backlighting.

Lots of confusion, I just couldn’t get two lines to work, so I went back to one line. I had momentarily wondered why I couldn’t get any decent contrast on the screen when trying to use two lines and the lcd.begin() line in my code.

I wondered if it was just my poor connections, so I tried a bit of soldering, but it didn’t help.

I went back to the drawing board, trying different wiring set up again.

Still not the effect I wanted.

I can’t seem to get the correct contrast when using the lcd.begin() line, that is to say that at a very severe angle it’s possible to read the screen, but under normal viewing it’s no where near what it should be (as pictured above). I didn’t post a picture of that because it basically just looks like the backlight is on with nothing on the screen itself. I couldn’t find an answer online, so I’m going to try this again with a different LCD. Although it could be a number of other things, this seems to be the simplest way to move forward. All these screens are based on the Hitachi HD44780 LCD, so it shouldn’t be an issue, but I’m not sue what else could be causing the problem at the moment… As frustrating as it can be sometimes, I think troubleshooting is where I learn the most.

Here’s a bit of an annotated bibliography :

http://www.arduinoprojects.com/node/13 (for whatever reason, this was the most successful wiring setup, though I have my suspicions that I messed up the contrast at some point due to my shoddy and impermanent wiring)

http://arduino.cc/en/uploads/Tutorial/lcd_schem.png (a diagram for the wiring setup recommended on the Arduino site)

http://www.jamie.net/tag/arduino/ (a quick example of using the 4-bit LCD library, I haven’t tried it)

http://dawes.wordpress.com/2009/12/23/twitter-to-lcd/ (interesting project connecting twitter and Arduino)

http://blog.tinyenormous.com/2008/12/02/arduino-based-rss-reader-with-lcd/ (lots of interesting projects, hooking up Arduino + Twitter and Gmail + Arduino using Python)

http://www.alfonsomartone.itb.it/kwztcq.html (some helpful troubleshooting stuff)

http://www.arduino.cc/en/Reference/AnalogWrite (analog write, I used this to correct the contrast problem I had)

http://arduino.cc/en/Reference/LiquidCrystal (LCD library for Arduino)

As part of a Canada Council for the Arts Inter-Arts Research and Creation grant I received, I will be documenting my work on the project through here, as I anticipate it will cross over into other projects we work on and came out of past projects we’ve completed.

This project comes out of Broken City Lab‘s previous work on Text In-Transit, where I’m hoping to open up a continuing flow of those kinds of texts in relation to a public space like a bus, or bus stops, or the downtown terminal. It’s likely that we’ll be working with Transit Windsor again on this project as it moves along. The project will connect this kind of publicly-engaged work I’ve done with BCL with some of my digital work I’ve done in the past.

The project is going to involve a lot of experimenting with Arduino-controlled LCD screens, and efforts towards capturing sms text messages, twitter updates, and emails and pushing them all into an LCD display. This will be the foundation of the project anyways.

I’m assuming this is going to involve a combination of interfacing Arduino with Max or Processing and using Perl or maybe PHP to do the text processing (depending on how involved it is), though it may end up taking another route altogether, but that’s what this time is for. I’ll be spending the next few months working through these aspects of the project, while also building towards an approximation of a public installation. I’ll spill more details as time goes on, and I’ll be documenting my progress, as I’ll undoubtedly need notes of my own, and why not keep them on here?

For now, I’ll be working through some basic tutorials, and eventually heading up to InterAcces for some of their workshops.

I would like to thank the Canada Council for the Arts for their generous support in this project. I’ll be acknowledging their support with their logo on each post that I write while documenting this project.