Electronics Blog - Ramblings from the Labz

Tiny DIY CNC Laser Cutting using old DVDs: don’t repeat my mistakes

The idea to document a failed project is not mine. When I read this post by Hackaday, I realized that I do have a project that failed which I don’t want to simply trash. Some valuable insights have been gleaned while working on it and I am planning to reuse many of the parts and the software in a different project. I have so many DVD drive parts now that it would be silly not to make another attempt at building a DVD CNC laser cutter, but it will definitely be designed differently, thanks to the lessons learned. So, that’s how this post came about.
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ATtiny13 POV display: same hardware, different message

St. Patrick’s Day is coming up and I thought it’s already time to update the original Valentine’s Day POV display with a new message and make use of the second PCB I had done at BatchPCB. Also, fortunately, John “smeezekitty” (the author of the Attiny13 core used for programming it in Arduino IDE) stopped by my blog and pointed out to an issue with the original firmware, which prompted me to take another hard look at it and the result has been a saving of whopping 20 or so bytes – it was just enough to fit the word “BEER” which, as I mentioned in the original post, we did not have any space in flash left for. Well, now we do and below is the new software Read the rest of this entry »

Manually controlling bipolar stepper motor with Arduino and EasyDriver

Stepper motors are great for accurate positioning because they move in discrete steps – a feature that makes them very appropriate for CNC software control. But every once in a while you have an application where you need to press a button and rotate some kind of a jig at a preset angle or move something a preset distance if it’s a stepper-driven linear stage. So, I decided to modify an earlier Arduino sketch I wrote for testing the world’s smallest stepper motor to make it a bit more useful (and clean any bugs in the process). Keep reading to see what came out … Read the rest of this entry »

Valentine’s Day POV display using ATtiny13 and Arduino IDE

Valentine's Day Chocolates with a message!

Valentine’s Day Chocolates with a message!

There’s nothing out there that says “I love you!” quite like a box of chocolates that actually says “I love you” (or “I ❤ U” as it were). Here is a quick electronics project that takes less than 2 hours to complete and makes a nice Valentine’s Day present. It is based on what has lately become my favorite small MCU – Atmel Attiny13 – and the software was written using my favorite development environment – Arduino IDE. So, keep reading for the schematic, the software, the build pictures and a small video showing the message slightly better than a still picture can Read the rest of this entry »

ATtiny13 12-LED blinker with motion detection and scripted blinks

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I can hear you screaming:”Not another LED blinker!” and yet here it is, packaged into yet another transparent Ferrero Rocher chocolate box, just like the first one. Why another ATtiny13 LED project? I needed to change the software to add a new feature and I had another box stashed away after Christmas – that alone should have been a reason enough 🙂 Additionally, I have to admit right here that there will likely be one more post that includes an ATtiny13, LEDs and chocolates before I let it go (soon, I promise) and move onto more serious things, such as the DVD-CNC project that’s been languishing on and off my workbench for more than a year now.

That said, if you are still interested in programming ATtiny13 with the Arduino IDE to blink 12 Charlieplexed LEDs, respond to motion (shaking) and have the LED on/off sequence scripted in an orderly fashion rather than random or simply 1 through 12, then read on! Read the rest of this entry »

I spent $2 to build a working Van de Graaff Generator and generate some sparks

Van de Graaff generator from found parts and a $2 M&M'S candy tin

Van de Graaff generator from found parts and a $2 M&M’S candy tin

When I was a little boy I was fascinated with static electricity and played a lot with sparks and attracting little pieces of paper to a plastic comb brushed through my hair. The comb was later replaced by an ebonite rod, also brushed through my hair, which my mother, a school physics teacher, brought home. It was great fun but brushing one’s hair gets old quick and, perhaps more importantly, some 30 years later it’s become crystal clear to me that human hair won’t always be so readily available for my static electricity experiments. Unless someone else volunteers theirs. And so it has become obvious: I needed to break my dependence on human hair as the source of high voltage energy! 🙂

Robert Jemison Van de Graaff to the rescue! His ingenious generator, developed in 1929, appeared to be a perfect replacement of the hair/comb generation technology, and it looks super cool doing it, too, with its tall column and a shiny metal sphere at the top! So, finally, some 30 years after I first read about Van de Graaff, I decided to take action and here is what came out … Read the rest of this entry »

Using Atmel AVRISP MKII programmer in Ubuntu

This is a quick follow up on an eariler post describing installation of Atmel AVRISP MKII programmer on a Ubuntu Linux computer. The original post was based on Ubuntu 10.10 and several small changes have sneaked up on us during the upgrade to Ubuntu 12.04
Here are the changes: Read the rest of this entry »

MSP430 in 64-bit Ubuntu 12.04 Linux – the Arduino Way

Programming MSP430 microcontrollers in 64-bit Ubuntu 12.04 Linux

Programming MSP430 microcontrollers in 64-bit Ubuntu 12.04 Linux

I recently had a chance to take a closer look at programming a new (to me) familty of microcontrollers – MSP430 by Texas Instruments. The opportunity came courtesy of Newark, which is where the TI MSP430 Launchpad Development Board can be purchased on their Analog & Embedded Catalog website. I’ve had access to TI MSP430 development boards before but, since I ran a Linux shop here, the hurdles of using the stock Windows-based developing environment were too much for me and I never actually got to play with them and I’ve pretty much given up on TI until this opportunity came along. Much has changed since then, so keep reading if you are interested in working with MSP430 in Linux Read the rest of this entry »

Laser Diode Driver with TTL Control. PCB V2.0 is ready.

Laser Diode Driver with TTL control. PCB V2.0, populated

Laser Diode Driver with TTL control. PCB V2.0, populated

This is another one of my belated updates. It has been about 3 months now since I’ve received the boards for the updated version of the laser diode driver from Olimex. However, I haven’t had a chance to work on any project that required a laser driver until just recently and so the boards were not populated and tested for the longest time. Finally, I can report that the design works, here are some pictures and there’s the Eagle board file for the PCB later in the post. Read the rest of this entry »

Belated 2012 Transit of Venus report

Sun projection with Venus shadow at 19:20:51 EST

Sun projection with Venus shadow at 19:20:51 EST

Although most of the posts you see on this blog are about electronics, hence the name: Elabz, I can’t resist the urge to post about of my other hobbies here. I haven’t done it before in all of the three year history of this blog but from this point onward my visitors are going to have to endure a non-electronics post every once in a while.

Astronomy is one of those not-yet-covered-here hobbies of mine and one of the rarest, easy to observe and just overall interesting astronomy events has just happened recently – the June 5, 2012 Transit of Venus. Since I had a camera handy, I had to snap some pictures and brag about it here 🙂 It was the very first time I saw an image of the Sun projected through optics and it was a rather illuminating experience, pun totally intended. Read the rest of this entry »