micsaund.com » Electronics http://www.micsaund.com Mike's World of fun stuff (pinball, games, electronics, amusement parks, computers, more) Sun, 06 Jun 2010 20:37:07 +0000 en hourly 1 http://wordpress.org/?v=3.0.1 Cheap, almost perfect iPad case http://www.micsaund.com/2010/06/06/cheap-almost-perfect-ipad-case/ http://www.micsaund.com/2010/06/06/cheap-almost-perfect-ipad-case/#comments Sun, 06 Jun 2010 20:34:59 +0000 micsaund http://www.micsaund.com/?p=1096 iPad and the case side by side

Showing the size of the iPad compared to the case


It seems that nearly anything with the word "iPad" on it commands a price premium, including carrying cases. Well, I found an alternative case that is nearly perfect for the iPad and it costs less than $15!

I was down my my local MicroCenter last night and figured I'd stop-in and see what they have. Those of you with Fry's stores nearby don't know how lucky you are. MicroCenter comes close, but still...

Anyway, I wanted a carrying case for my new iPad and I had read that you could use the netbook carrying cases and save quite a bit of money. So, once in MicroCenter, I went to their Apple section and grabbed an "iPad case" and proceeded to the massive shelf piled with dozens and dozens of netbook/laptop cases.

After a bit of digging and thinking about what I wanted, I avoided one of the fully featured "mini laptop" bags as that defeats the purpose of the iPad. Plus, there aren't any ports/etc. on the iPad to speak of, so I figured there'd be little reason to haul a bunch of crap around in the bag.

Thus, I opted for a more slimline type sleeve/case. There were several to choose from in the 7-10 inch "netbook" range which would work for the iPad. However on my way to the checkout, I noticed one last case that made me dump the neoprene sleeve - and it was $5 cheaper!

I found a black nylon Case Logic 7-10.2" netbook case with bonus hard drive case. The actual case the iPad goes into is made from a tasteful black nylon cloth (like a suitcase) with a couple "leather" accents which actually look decent. The case is lightly padded (probably 1/8" or so foam) and almost fits as though it were made for the iPad. It's a bit taller than the iPad (maybe 0.75 inches) but nothing really noticeable. And, even with the InCase rubber protector I've got on my iPad, you can easily slide it into the case because the zipper goes almost all the way around the top and one side.

The bonus hard drive case I figured would be handy to hold the iPad power adapter and USB cord.

Best of all this case was $14.99 retail at MicroCenter and it's even cheaper at Amazon ($12.99 as of writing this)! For comparison, the cheap neoprene iPad sleeve I was using for sizing in the store was $29.99!!!

I'm very happy with this case, it's fit, and just how it feels. With the solid, weighty iPad inside, it fits in your hand like a small text book. Oh, and it's about as thick as the iPad AC adapter when zipped shut with the iPad inside.

The bonus case can hold the iPad adapter and cable The bonus case can hold the iPad adapter and cable Photo showing the information on the case's box The back side of the case Showing how the case opens and the interior iPad and the case side by side Overall photo of the case's rear panel packaging The front panel of the case's packaging Showing the iPad, case, bonus case, and iPad adapter and cord Showing the tag on the case stating that it's airport security compliant Tag from the packing showing airport security compliance Close up of the case's UPC code and model iPad sitting on top of the case for size comparison Showing the iPad inside the case Showing iPad AC adapter next to case for thickness Showing iPad AC adapter next to case for thickness iPad and case side by side iPad on top of case ]]> http://www.micsaund.com/2010/06/06/cheap-almost-perfect-ipad-case/feed/ 2 Awesome spinning LED sphere project http://www.micsaund.com/2010/05/13/awesome-spinning-led-sphere-project/ http://www.micsaund.com/2010/05/13/awesome-spinning-led-sphere-project/#comments Thu, 13 May 2010 17:11:30 +0000 micsaund http://www.micsaund.com/?p=1071 LEDs
Check-out this awesome LED persistence of vision project some guy made from leftover junk in his parts box. The video (inside the post) is worth a million words.


This project features a total of 9 slip rings to provide power to the various spinning elements in the project. The effect once it gets going is pretty cool. A minute or two into the video there are some patterns which are very interesting.

Does that make you want to grab a microcontroller, a bunch of LEDs and get building? :)

]]> http://www.micsaund.com/2010/05/13/awesome-spinning-led-sphere-project/feed/ 0 FPGA board emulates classic platforms http://www.micsaund.com/2009/05/04/fpga-board-emulates-classic-platforms/ http://www.micsaund.com/2009/05/04/fpga-board-emulates-classic-platforms/#comments Mon, 04 May 2009 22:28:36 +0000 micsaund http://www.micsaund.com/?p=828 FPGA Replay board uses an FPGA to play classic arcade games

FPGA Replay board uses an FPGA to play classic arcade games


This cool projects aims to take the various FPGA-based arcade platforms and run them on a common piece of hardware, thus letting you play many games and platforms without having tons of equipment sitting around.


I've written here about various FPGA arcade and emulator projects, such as the Minimig Amiga 500 project. All of these projects are using a hardware programming language like VHDL or Verilog to implement the circuitry of classic arcade and computer platforms on a regular, (relatively) cheap field programmable gate array (FPGA).

There is one project, though, which is attempting to create a single hardware platform that you can buy which will run many of these independent projects. Currently, the board is still in the design and debug phase, with only a few developers having them, but eventually, the FPGA Replay board will be offered as a pre-assembled unit which you can download the various games onto, or work on your own pet projects.

Currently, the games supported by the FPGA Replay include:

  • Scramble
  • Frogger
  • Asteroids Deluxe
  • Pac Man
  • LadyBug
  • Space Invaders
  • Galaxian

I'll be keeping an eye on the progress of the FPGA Replay as I think this would be really fun to play around with, if only for the games. But, it could also be a challenging project to take one of my favorite games (like Robotron or Joust) and try to create the VHDL code to actually run it. I suppose that's something to add to my ever-growing list of "long term to-do" projects ;)

]]> http://www.micsaund.com/2009/05/04/fpga-board-emulates-classic-platforms/feed/ 1 Digital Apollo – the story of the first computers in space http://www.micsaund.com/2009/03/26/digital-apollo-the-story-of-the-first-computers-in-space/ http://www.micsaund.com/2009/03/26/digital-apollo-the-story-of-the-first-computers-in-space/#comments Thu, 26 Mar 2009 15:38:19 +0000 micsaund http://www.micsaund.com/?p=805 Digital Apollo book covers the computer technology of the Apollo space missions

Digital Apollo book covers the computer technology of the Apollo space missions


Have you ever thought about how amazing it was when the Apollo space missions actually took someone to the moon considering that they didn't have the fancy technology we have today? This book recounts the design and use of the on-board Apollo digital computers.


In the 1960s, the United States had a focus: beat the Russians to the moon. Amazing feats of engineering and bravery were accomplished with the entire country backing the NASA Apollo space program. To this day, I have the highest respect for the people who worked on these projects and achieved such amazing goals without the help of modern-day computers and their ability to run endless simulations and model every possible scenario. Those engineers and astronauts in the 60s did it with clear thinking, hard work, and solid design principles.

One of the amazing pieces of technology which resulted from their work was the Apollo Guidance Computer (AGC) on-board computer which helped the Apollo missions navigate properly. These ancient (in computer time) machines were built from individual transistors and used a type of memory almost nobody has heard of which uses magnetic coils wrapped around a piece of iron. The AGC processor module even had interrupts like modern processors, which allowed certain events to grab the computer's attention for immediate handling.

These computers weight upwards of 70 pounds and had the computing power available today in a small $2 AVR or PIC microcontroller. It's amazing how far computers have come in the past several decades. Yet, while I do enjoy using microcontrollers to build my projects, there's something "utilitarian" about them -- they're not exciting or pushing the envelope like the Apollo Guidance Computer did. Those engineers that got to work on the Apollo missions truly were leading the charge into the future and we are the benefactors of their work today.

Check-out Digital Apollo and read the excerpts to decide if you want to take a tiny step back in time.

Thanks to SparkFun for letting me know this book is available.

]]> http://www.micsaund.com/2009/03/26/digital-apollo-the-story-of-the-first-computers-in-space/feed/ 0 Add web access to your electronic projects and hacks http://www.micsaund.com/2009/02/19/add-web-access-to-your-electronic-projects-and-hacks/ http://www.micsaund.com/2009/02/19/add-web-access-to-your-electronic-projects-and-hacks/#comments Fri, 20 Feb 2009 02:32:10 +0000 micsaund http://www.micsaund.com/?p=760 Add a web interface to your electronics projects easily and inexpensively

Add a web interface to your electronics projects easily and inexpensively


Easily and cheaply add a web-page interface to your next hacked gadget or microcontroller project with these simple, pre-built modules.

More and more devices in our everyday lives are connected to a network. It used to be that it was just MIT nerds who were hacking their dorm Coke machine to report the temperatures and remaining cans via a webpage. Today, things have changed. Many homes have some sort of network installed. There are network connected security cameras, network connected weather stations, and much more.

However, getting a device on a TCP/IP network is not trivial. You have to have a software stack and lots of other things that frankly have kept me from ever building a project which could communicate over the network.

Enter the EZ Web Lynx modules. These are compact, inexpensive modules which will allow your various homebrew electronic projects to have their own webpage to report data or even control things. The modules are available in 3.3v and 5v versions, so they'll work with nearly any common microcontroller no matter whether you prefer AVR, PIC, Renesas, Rabbit, or even old school 6502 if that's how you roll.

The modules have digital/analog inputs thanks to their on-board controllers and make it trivial to connect sensors to monitor the deep freezer in your basement or the kegerator in your garage. Of course, if your project is more ambitious, you can feed the appropriate signals into the modules via your microcontroller - no TCP, HTML, or other complicated stuff required.

Check-out the EZ Web Lynx modules -- they start around $50 each, but drop very quickly in price if you can order a small quantity with some friends in the local robot club (or MIT nerd dorm ;) )

]]> http://www.micsaund.com/2009/02/19/add-web-access-to-your-electronic-projects-and-hacks/feed/ 0 Retro 8 bit BASIC computer is a blast from the past http://www.micsaund.com/2008/12/25/retro-8-bit-basic-computer-is-a-blast-from-the-past/ http://www.micsaund.com/2008/12/25/retro-8-bit-basic-computer-is-a-blast-from-the-past/#comments Thu, 25 Dec 2008 19:21:12 +0000 micsaund http://www.micsaund.com/?p=714 Retro Computer System runs BASIC
Get in the computer time machine and travel back to the days of a simple computer that's programmed in BASIC and boots in under 1 second. Or, you can buy the Retro Computer System.

Many readers of this site will have had at least a bit of experience with the personal computers of yore, such as the Commodore 64, Apple II, Atari, or any number of other similar systems. The machines from that era were simple by today's standards but they had a certain charm and there was certainly a level of variety in the computer 'ecosystem' that made the various models vastly different from each other (for you young'uns who've only ever used Windows, there was a time in the ancient computer past where programs would not run on every machine you could buy!)

All of those early computers had several things in common. You'd turn them on and almost instantly, you were at a prompt ready to begin writing a program or doing whatever else you wanted. There was almost always a BASIC programming language that formed the base of the user interface. There was often an "expansion port" where you could hook-up either home-brew circuits or store bought goodies. It was very different from today.

Well, if you want to re-live those glory days of the simple computer, Multilabs has you covered with their new Retro Computer System. It's a simple 8-bit system that boots straight into a BASIC language prompt, just like the old C64. There are numerous ports such as a PS2 keyboard port, DB9 digital joystick port for use with Atari style sticks, and of course an expansion port. Video is output via an ezVGA chip, so you can use the Retro with a regular VGA monitor rather than tracking-down an ancient composite monitor which most of us don't have any longer.

The BASIC language used on the Retro will look familiar to anyone who's used any of the computers I mentioned above. It even uses line numbering! Here's a sample from the sample Eliza-esque demo:

Screenshot of Retro Computer System demo program


430 COLOR 57:LOCATE 0,9:PRINT CHR$(128)
440 LOCATE 4,8:PRINT CHR$(129)
450 COLOR 22:LOCATE 0,11:PRINT CHR$(130)
460 LOCATE 4,12:PRINT CHR$(131)
470 COLOR 63:LOCATE 26,0:PRINT "USER INTERFACE"
475 LOCATE 19,13:PRINT "DOCTOR RETRO RESPONSE"

Multilabs sells a blank PCB that plugs into the expansion port and allows you to interface relays, sensors, and anything else to use with the Retro. Since there isn't an over-complicated gigabyte-sized operating system getting in the way, you can address your expansion port hardware directly without any drivers, so you can really get down to business working on your projects!

The Multilabs Retro Computer System is $100 which is relatively cheap for the functionality you get. If you don't have any PS2 keyboards, don't forget to order one (I think I dumped all my old keyboards just over a year ago - it figures!) I may put a Retro in my ever-growing to-buy list but if Multilabs wants to send an eval unit, that's cool too :) . I certainly miss the simplicity of my C64 and being able to trivially write programs and just have fun with a computer. If you have any experience with the Retro, please leave a comment below!

]]> http://www.micsaund.com/2008/12/25/retro-8-bit-basic-computer-is-a-blast-from-the-past/feed/ 0 Simple DIY microcontroller based video game console http://www.micsaund.com/2008/09/02/simple-diy-microcontroller-based-video-game-console/ http://www.micsaund.com/2008/09/02/simple-diy-microcontroller-based-video-game-console/#comments Wed, 03 Sep 2008 02:48:38 +0000 micsaund http://www.micsaund.com/?p=697 Homebrew microcontroller-based video game console
This open-source hardware and software project shows just how much can be done with modern microcontrollers. It implements a fully functioning, NES-class programmable video game system in just a couple chips, a few resistors, and some other miscellaneous components.


This is a neat project that actually looks fairly powerful! Using only an ATmega644 microcontroller and an AD725 RGB-to-NTSC converter for major components, the Uzebox game console is a build-and-program-yourself project that is pretty simple, but also very impressive in the resulting product.

The Uzebox open-source hardware and software project

Hardware-wise, the console offers 4K of RAM and 64K of program space, with four channels of wavetable sound. Control inputs are setup for NES pads, but you could choose any similar input scheme since those old pads were just switches and not the complicated serial/analog stuff on modern commercial consoles.

The software is interrupt-driven, which prevents the programmer from having to count cycles, so it's not quite as challenging to program as an Atari 2600, but should still be fun. You can access up to 256 colors thanks to the resistor-ladder DAC setup while the AD725 handles the heavy lifting to convert the signal to a standard TV-compatible NTSC signal.

Overall, it looks like you write some code that results in a very NES-class game. For example, look at the video of Tetris running on the Uzebox below and you'll see that it's definitely capable of NES-class games.



Not too shabby for an ATmega644 running at 28MHz! If you want to learn more or build your own, check-out the Uzebox retro video game console project. If you build one, let me know how it goes - I'm thinking I might take the plunge and try it myself!

[Thanks]

]]> http://www.micsaund.com/2008/09/02/simple-diy-microcontroller-based-video-game-console/feed/ 2 Build your own FPGA based Amiga 500 clone http://www.micsaund.com/2008/07/22/build-your-own-fpga-based-amiga-500-clone/ http://www.micsaund.com/2008/07/22/build-your-own-fpga-based-amiga-500-clone/#comments Wed, 23 Jul 2008 03:58:56 +0000 micsaund http://www.micsaund.com/?p=633 An Amiga 500 designed in an FPGA
The Amiga 500 was one of the very popular "non-IBM" choices back in the day thanks to its great selection of games powered by then-cutting-edge graphics chips and incredible stereo sound processors. If you long for the days of the Amiga and have a desire to build a project, this open-source hardware design might just what you need!

We've come a long way since 1987, which was the year the incredible Commodore Amiga was introduced. The Amiga was literally ahead of its time with 4096 color graphics, stereo sound, built-in speech synthesis and of course, a graphical user interface. Remember that back then, the IBM PC compatibles had mono or four-color CGA graphics, a PC speaker that still to this day only goes "beeeep!" and a pricetag that was at least 5X the Amiga. Yeah, I'm one of "those guys" who hated IBM clones back then and frankly, I still stand by that - they sucked back then - admit it ;)

Anyway, there's a GPL open-source hardware project out there called the Minimig which incorporates a fully Amiga 500 compatible design onto a Xilinx Spartan3 FPGA housed on a 12cm x 12cm board. The board includes PS2 keyboard and mouse connectors as well as the obvious video-out and sound. Being an open-source project, you are free to take the design and hack it however you see fit, and several people have done exactly that and created a board that fits into a standard ATX case, a board you can buy that's pre-built, and more. Pretty cool in my opinion!

Check-out more about the Minimig Amiga 500 project and if you are up to it, build your own or even contribute to the project to help fix the remaining minor bugs. After that, you can get back to your game of Lemmings!

]]> http://www.micsaund.com/2008/07/22/build-your-own-fpga-based-amiga-500-clone/feed/ 1 Who knew plasma globes could be hacked? http://www.micsaund.com/2007/12/24/who-knew-plasma-globes-could-be-hacked/ http://www.micsaund.com/2007/12/24/who-knew-plasma-globes-could-be-hacked/#comments Mon, 24 Dec 2007 22:48:27 +0000 micsaund http://www.micsaund.com/2007/12/24/who-knew-plasma-globes-could-be-hacked/ Customized plasma globe with a microcontroller
Remember those plasma/lightning globes, primarily from the late 1980's and early 90's? They were "the thing" back then, but I can't say that I ever thought about hacking one to see what could be changed. Fortunately, someone else has!

Surely you have seen a plasma globe: they are the glass spheres of varying sizes that have colored electrical arcs dancing around in them. You can touch the globe to affect the movement of the lightning. Yeah, you remember ;)

The standard mode of operation for a plasma globe is either "on" or "pulse to audio" which is supposed to result in some kind of music-synchronized disco effect (which honestly, never worked that great in my experience).


ATmega8 microcontroller runs the plasma globe
Well, it appears that you can alter the frequency of the power supply feeding the high voltage into the globe to create various effects. Combine that with a microcontroller, and you can have a flexible, easily modified programmable plasma globe which you can experiment with and zone-out to when the mood strikes you.

In the video below, the color of the lightning can be changed from green at low frequencies to purple at high frequencies. The movement and behavior of the electricity changes with the frequencies as well. Using an ATmega8 microcontroller, the guy created a system that can be programmed and adjusted via a computer interface, but will also download the programs and settings to the microcontroller allowing un-tethered operation. Pretty cool!

Just make sure that you're careful around the high voltage supply so you don't zap yourself! :D

Read more about the microcontroller controlled plasma globe.

Thanks Hacked Gadgets.

]]> http://www.micsaund.com/2007/12/24/who-knew-plasma-globes-could-be-hacked/feed/ 2 PIC microcontroller based video game system http://www.micsaund.com/2007/10/23/pic-microcontroller-based-video-game-system/ http://www.micsaund.com/2007/10/23/pic-microcontroller-based-video-game-system/#comments Tue, 23 Oct 2007 16:39:06 +0000 micsaund http://www.micsaund.com/2007/10/23/pic-microcontroller-based-video-game-system/ Home built PIC microcontroller game machine
Using a trio of PIC microcontrollers, this guy built a fully functional video game which uses analog paddles and has more gameplay than the usual Pong type stuff you typically see from PIC games.

People have been making very simple pong type games using Microchip PIC microcontrollers for some time. However, due to the very limited power of the PIC, you typically don't see anything involving sound, moving backgrounds, more advanced gameplay, or animation.

John Sachs Beeckler decided to take PIC-based gaming to the next level, though. His design uses three PICs to sub-divide the tasks required for making a full-featured game. There is one master processor (16F877) which controls the overall system and performs the game logic, while two additional PICs (16F84 and 16F877) handle the graphics and sound generation.
Home built PIC microcontroller game machine schematic

The main code was written in C but the graphics generator is hand-coded in assembly to meet the strict requirements of generating the video signal (remember programming the Atari 2600?) The sound data is pulled from an external EEPROM and converted to the analog audio signal using a resistor network. The entire codebase fits in 8K of FLASH and efficiently uses the minimal ROM and RAM available on the PIC microcontrollers.

The code and design has been open-sourced, so you can download everything and use it in your own projects or to just build your own identical game if you want. One thing I'd suggest changing about the design is how he wired everything up -- what a mess! ;) Check-out the Alien Slaughter home built PIC game system for more details.

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