So far the trend has been to build more and more computing power into the devices so they can run plenty of applications. That’s not where things are headed though.

Switching gears for a second back to traditional Desktop computing: Pano Logic [LINK] make a tiny little box that completely virtualizes the computer. Huh? what’s that? It means your operating system doesn’t run on this box, it runs elsewhere, usually in a data center someplace, accessible through the Internet. The tiny little Pano box just communicates back and forth with this instance of your computer, sending keyboard clicks, mouse movements and clicks to it, and getting back a screen image to display.

This technology is not new. I’ve used VMWare and Virtual PC to run various operating systems for years now. When you need to “upgrade” you just change the configuration of the virtual machine. Need more memory? Just change a setting in the config.

Folks like Amazon have been building out a very robust “cloud” based computing platform over the last 5 years (the Elastic Computing Cloud) which is targeted at web-site hosting. It’s pay-as-you-go with very rapid scalability available on demand. This means that web startup I worked on in 1999 that paid $4,000,000 for spanking new managed hosting with EMC and the whole nine-yards could’ve saved that and grown organically. It’s a great system.

Back to Cell Phones, here’s where I see things going: There’s a certain critical mass in terms of device-technology you need to attain and I believe we’re there. Devices have touch-screens, crystal clear displays, small form factors with built in video cameras and support for WiFi aswell as multiple cellular networks. We’re good to go.

The next step is to virtualize the phone operating system. Separate the software that normally runs on the phone from the thing that is the phone device. Have the phone run in the cloud and the device be just a proxy to that operating system. This will enable a number of things.

1. Your phone will no longer be tethered to your device. Huh? Yeah, you’ll be able to leave your phone “thing” at home, yet still access your phone from any internet access point.
2. Your phone will now have infinite storage.
3. Your phone can now run infinite applications, simultaneously.
4. Your data is now accessible from anywhere. You can synch your phone’s data to your home PC or Media Center or xBox and so on.
5. Upgrades will no longer mean waiting for a new phone device.
6. The focus will rapidly switch to the operating system and so Google Android will have a huge advantage whereas the iPhone will lose its hardware-specific advantages.
7. Voice over IP will replace the phone network. Phones will maintain GSM, CDMA, Edge etc. connectivity and likely still use these for some time to come but ultimately the Internet connectivity will be what matters. Things like Skype will merge into the cell-phone business.
8. Battery life will either be extended or stay the same. I don’t know about you but my phone gets HOT when I use it. This is due to the phone’s CPU cranking away. If the bulk of the processing were running remote, I’d imagine the battery’d be cooler and spend less energy powering the local CPU. I’m not sure about this one though since connectivity itself might increase and eat up power.
9. The phone can run…even when it’s OFF. Yes, of course, the device is no longer the thing that controls when the phone operating system is running. You could have the remote operating system actually wake up the phone device when a call comes in. Pretty cool.
10. No more downloads. Your device never needs to receive anything from anyone, it’s all sent to the remote operating system. The device communicates exclusively with it.
11. Let’s face it, your desktop’s headed this direction. Ultimately your Phone and your Desktop will be able to share common storage, like a network-attached disc. Same thing with your DVR. You’ll be accessing TV shows you recorded at home from your cloud based phone. Everything’s backed up. The world will slowly accumulate thousands of copies of digital junk…
12. Because data and storage are now unlimited, a new trend will emerge which is to capture and log everything you do all day. This is more tied to battery life but I could envisage a cell phone that records its GPS position, and takes a picture every five minutes, shoots these up to the cloud. I’m going to call this “Life-logging” or “Flogging”. The world of the “Blogger” will be obsolete. (ok I’m going out on a limb here a bit).

The road is clear for this to happen. The technology is there, the market is certainly there and so of course the opportunity is there. The question now is who’s going to be first?

If I had to put money on it my guess would be a combo of HTC + Google.

From Steve’s site:

“Big Mess o’ Wires 1 is an original CPU design. It does not use any commercial CPU, but instead has a custom CPU constructed from dozens of simple logic chips. Around this foundation is built a full computer with support for a keyboard, sound, video, and external peripherals.

My original goals were:

• Build the CPU from scratch, primarily using basic 7400-series logic. No 6502, Z-80, etc.
• Keep the hardware complexity to a minimum. I’m not an electrical engineer.
• Be capable of running “real” programs, not a 4-bit CPU or toy machine.
• Provide a way to interface with a PC.
• Be fast enough to run interesting programs interactively”

Interestingly I also used the 74HC595 shift registers on my LED matrix project.

Steve’s project doesn’t use soldering but rather each wire connecting the chips is wound by hand around a special gold leg on the proto board. This is an “old school” technique which takes a lot longer than soldering but if you make a mistake it’s much easier to recover from.

Things like this always fascinate me when I contrast to software development in the “real world”. Here’s a guy that had a direction, knew what he wanted to achieve and set about doing it. It’s just one person so it took a long time but he got there.

If you wanted to get 2 people to build the same thing, working as a team, my guess is the likelihood of success goes drastically down. In fact on a project like this with the addition of that one extra person you’re probably going to fail the first time.

So why is that?

Contrast this with the process of industrial ship building or air-liner development. Those projects involve literally thousands of people, each doing a small job. In the case of the air force or Department of Defense you now have thousands of vendors. And it seems from the Discovery Channel that those projects generally finish on time.

Why is that?

The common thread is hard to pin down but to me it’s people who know what they’re doing.

The ship building scenario is a very long process but infinitely broken down into minute detail. Each component, each step is itself extremely well defined and well understood. So in spite of its size, the ship building process has

• a LOW number of unknowns
• very RIGID requirements
• and a LARGE number of people and moving parts.

Now in the case of how to build a CPU from scratch, starting out I’d say Steve knew very little. I would venture (and it’s no reflection on Steve) that almost the entire process was an unknown. So how was he successful?

In contrast to the ship example he had

• a HIGH degree of unknowns
• very FLUID requirements
• a LOW number of people

Of course things are never this clear cut which is why software development is so tricky. You need to constantly manage these three variables of Unknowns vs Constraints (requirements) vs Headcount and keep them in balance if you’re gonna be successful.

And so I draw my conclusion; Any time you have a HIGH degree of unknowns with RIGID requirements and a LARGE number of people you are destined for FAILURE.

The corollary is any time you have a LOW number of unknowns with FLUID requirements and a LOW number of people, you are destined for SUCCESS.

I know which team I’d like to be on.

I started with the LED Matrix component itself. I used an RGB 8×8 common anode matrix from LedSee (only $10 on ebay). The matrix takes 32 pins: 8 anodes, 8 cathodes for Red, 8 for Green and 8 for Blue. Then I had an arduino Diecimila which was about $25 I think but you can use any ATMega based board.

A little googling revealed that a thing called a Shift Register could help me drive all those 32 pins using just a couple from the arduino. Shift Registers are cheap and easy to source. I used the 74HC595 IC.

The arduino website has a tutorial on Shift Registers which can be found here: http://www.arduino.cc/en/Tutorial/ShiftOut. This explains what they are, how they work, the clock, latch and data pins as well as how to chain them together.

After a few evenings of experimentation I knew I could drive 8 pins per 74HC595 chip. If I chained enough together I could drive all 32 pins. So I was set.

Next I drew up the schematic on paper. I played with a few prototypes using Breadboard until I had confidence that the circuit would work. This was a smart move as it turned out there was a problem. I found through experimentation that the Red LEDs were overpowering the Green and the Blue. I couldn’t figure it out since the code treated them all as equals. I went back to the reference manual for the LED matrix and found that the operating voltage of the RED LEDs in the matrix is actually lower than the Blue or Green.

I was able to even them out by introducing a higher resistor (330) into the RED cathodes than is in line with the blue and green (220 ohms). That was a true moment of enlightenment.

There’s a lot of wires so I put it into Visio. Here’s the result:

The blue, green and yellow lines go to the Arduino.

Next up I worked on the code. Besides turning the LEDs on and off I wanted to actually get different colors. I had no idea how to do this but it turned out Robert aka “MadWorm” had already figured it out: [LINK]. My code is essentially based entirely off of Robert’s so I won’t complicate or confuse you with my own extensions.

To better understand the ISR business, I’ll refer you this time to ucHobby [LINK]

The arduino supports an interrupt which is essentially a routine that runs in the the background, almost like a separate thread, from your code. This interrupt is what updates the Matrix pins and it happens very very fast. Even better is that it frees up the main loop of your Arduino sketch to do the interesting stuff like update the actual matrix data.

Pulse Width Modulation or PWM is essentially a way of simulating an analog output from a binary source. Huh? Wha?

If I turn on a Red LED I get red, if I turn on a Blue LED I get blue. If I turn them on both at the same time I get purple. What if I want to get some color in between? with this type of system you can’t get anything but 7 colors (R, G, B, RG, RB, GB, RGB). The only way is to turn on the LEDs partially. But an LED can only be fully on or fully off, how can you get a “partial” LED? The answer is PWM.

Pulse Width Modulation varies the time for which an LED is active. It’s still either fully on or fully off during that time, but if you think of that time as a wave, the “width” of the “pulse” during which the LED is active varies. Here’s a good visual:

The result is an ability to “mix” colors by different degrees and get a far wider range than the 7 possible combinations of RGB. The good news is this is all implemented within Robert’s ISR code above.

So I soldered away busily for three nights and in the end I had a nice little circuit board. Definitely not as small as it could be but good enough for a RevA.

At this point I had everything working nicely so I built simple case of Cherry/Lexan and four hex-head bolts to finish up.

That’s basically it! You can checkout the pictures below or find the video on Youtube. I had a lot of fun making this thing. It sits proudly on my desk today and although many have tried, no one can resist asking “what is that thing”.

The PWM is very tough to videotape but take a peek at the pics. Here’s my daughter playing with the prototype:

A resistor limits current. In the water analogy, current is the speed of the flow of water. But I never knew what a pull up/pull down resistor was. Until a few weeks ago when I started building a set of buttons for a project I’m working on…

Essentially a button is a switch, when the switch is closed the current flows, when it’s open the current doesn’t flow. Now if your switch is open, without anything driving the circuit, the value on the line is going to float all over the place, sometimes high, sometimes low. Any electrical noise will cause a change in the circuit. This causes a problem as when reading a value off the circuit you might think the switch is closed when in fact it’s just floating high.

The circuit on the left uses a pull up resistor. If Vcc is +5Volts, that goes through the 10k resistor and has nowhere to go but to pin 1. So when the switch is open, pin 1 is showing +5Volts (but very low current due to the 10k). Pin 1 will be steady, it won’t float up or down since it’s got some power to it.

When you close the switch, the current flows to ground. It’s always going to go to ground if it can so Pin 1 will show 0Volts.

The pic on the right is the pull down resistor. Same thing but the 10k resistor is between the pin and ground, causing it to “pull down” whilst the switch is open. Once it’s closed the majority of the current flows through the pin vs going to ground hence the pin reads +5V.

It’s making sense to me and now that I’ve actually built some stuff from scratch, I’ve actually experienced this voltage float and fixed it with a pull down. This blog will help me remember it in a year.

P.S. The Image is from “Resistance 2″ on the PS3. Pardon the pun.

Last night I got an email from Shawn over at [http://www.arduinofun.com/]. Shawn’s built a cool robot using various bits and pieces, including the arduino with Curious Inventor as his supplier. The coolest thing about this is he’s built it with his 11 year old son Drew. This is great on so many levels and I can’t think of anything better than mentoring a child in this manner.

I know my kids, Sydney and Ethan got a big kick out of my LED matrix/Processing project (checkout the video here [LINK]).

My next project is very ambitious;I’m thinking a CNC-style plotting/drawing thing. It’s another one the kids’d identify with. But right now parts are fairly scarce.

 Times are hard and I wonder if Curious’d sponsor me with some other free stuff? A few Stepper motors and a couple of Darlington arrays etc. would go a long way to getting me started…

They saw how things were linked together, how a click on the screen lit a dot on the matrix and it was simple enough but yet they could quickly make shapes and letters. They got a big kick out of it and I’m really glad to be able to expose them to science and learning at such an early age.

If you’re interested in a closer look at the matrix driver circuit, checkout the gallery here:

I used a modified version of the LCD arduino library and hacked the LCD Smartie Sketch using Orbital Matrix commands.

LCD Smartie is running the BigNum plugins. It shows Facebook news feeds, BBC Headlines, a Clock, local Weather and my Folding at home status (team 144824) among other things.

This was a fun project, not too much soldering and had a high reward vs time invested.

Here’s a video of the finished product.

Battery life sucks though and I couldn’t take signing up to iTunes just for phone access. That’s uncalled for. So what’s the competition? Verizon have some fairly blech looking clones (the LG Dash) but what I’d really like is an HTC device running Android [LINK]. Oh the tinkering I could do then. But it’s not out yet and no one knows when it will be.

It’ll probably take me six months to decide. I’m tempted to just get another basic deal. After all I don’t really need all thos whizz-bang features and I already have a blackberry for work.  What to do, what to do?

As a small project to get my feet wet with serial/parallel output, shift registers etc. I’ve set about building a 25 (5×5) RGB LED matrix display. I may extend it in the future to 7×5 for larger fonts.

I’m using circuit board from RadioShack to which I’m soldering the LEDs. I intend on using breadboard for the chips until I get the circuit figured out.

I have always struggled with my soldering skills. I could never get the solder to flow where I wanted. It just melts on the tip of the iron and gloms all over the place, everywhere but where I wanted it to go.

That all changed last night when I discovered what I think might be where I’ve been going wrong all this time. I’ve always heard that you heat the lead and let the solder flow onto it. That never worked for me. It just bubbles on the lead and "floats" over the pad.  I’ve also heard you should heat both the lead and the pad, but with that method I could never figure out how to position a chisel-head soldering iron to get them both hot enough.

So last night I tried heating the PAD with a "PENCIL" tipped iron. With this iron/method combo, the lead gets hot by default. After 2 seconds, the solder will flow like the wind and seems to gravitate around the lead, following the path of the pad.

So it took a while but last night I got 100 successful solder joints (25 LEDs, each with R,G,B and Cathode). Tonight I’ll bridge the pads and form a matrix circuit.

I am getting excited.

As a separate note; checkout this little browser add-on which enhances viewing images in things like Flickr, Picasa etc. [LINK], pretty cool.