Tool Hacks

3063 Articles

Pocket Multimeter Review

October 5, 2009 by 33 Comments

three_pocket_multimeters

Reader [Mikey Sklar] told us about a review he wrote covering 3 different models of pocket multimeters. We’re sure that you’ve had the same experiences we have being the go-to-guy or got-to-gal  for all things electrical. For our sort, having a multimeter on hand at all times has become an expectation.

[Mikey] looks at a model from ebay, Harbor Freight, and Radio Shack. Not surprisingly, the ebay offering doesn’t rate too well but does get the job done. We were surprised to read that he picked up the Cen-Tech model for about $10 at Harbor Freight. Although it may no longer be sold there (we haven’t checked) [Mikey] seems pretty happy with it so we’ll be on the lookout during our next tool-buying trip. We’re unfamiliar with the tiny Radio Shack 22-820 but we’ve always been happy with our larger 22-811. The 22-820 allows the probes to be folded up inside of the case cover for a truly pocketable package.

You can never have too many meters at your disposal and we’ll have to keep this article in mind the next time we’re shopping for another. Never used a multimeter before? Take a look at the tutorial [Mikey] linked to over at ladyada.

Power Generating Backpack

October 1, 2009 by 28 Comments

[youtube=http://www.youtube.com/watch?v=UL_CUbN9F7E]

In the military, you have to carry tons of stuff. This is something we hear and see all the time. They are always trying to come up with ways to reduce the weight or quantity of the things that you bring into the field. This power generating backpack harnesses the natural up and down motion of your steps to produce power. This could reduce the amount of batteries carried into the field greatly. That’s what they say anyway, how many batteries do soldiers normally carry around? Aside from that point, we think it is pretty cool. We could see using this to keep our cell phone or GPS charged on long hiking and camping trips. You could also build something of your own to work similarly.

How To Generate Font And Picture Header Files

September 29, 2009 by 19 Comments

custom_fonts_displayed

Displaying custom fonts or images on an LCD screen using a microcontroller usually requires quite a bit of work. We’ve used some readily available tools to make this a bit easier for your next project. Our python script will convert BMP files into a header file ready for use with AVR microcontrollers. We’ll walk you through it after the break. Continue reading “How To Generate Font And Picture Header Files” →

Connect A PS/2 Keyboard To A Microcontroller

September 29, 2009 by 10 Comments

[youtube=http://www.youtube.com/watch?v=vfIiLE0BhE8]

The guys at Nerdkits have put together this tutorial on connecting a PS/2 keyboard to a microcontroller. Though this tutorial is written for one of the kits they sell, you should be able to apply this to pretty much any microcontroller. It is also a lesson in using interrupts instead of polling. They have several pre built examples ready to download as well as source code for the basic setup.

[via HackedGadgets]

Tool Tip: Microcontroller Timer Calculator

September 28, 2009 by 11 Comments

uC_timer_calculator

In life and embedded systems timing is everything. Give [Frank’s] web-based timer calculator a try. Set your system clock resolution (in hertz making sure you account for any system clock divider), select your timer resolution and prescaler, then calculate based on desired ticks, overflows, or real time. He’s built this with the AVR chips in mind but it should be handy for any family of microcontrollers.

Of course none of this is rocket science, but if you’re trying to use one timer for two differently synchronized events this can save you a lot of trial and error time.

AVR Dragon Wiring Alternative

September 26, 2009 by 23 Comments

dragon_jumper_board

We love our AVR Dragon programmer. It is a small board with a lot of functionality: in-circuit serial programming, JTAG, debug wire, and high voltage serial programming. Unfortunately, out of the box it is not quite ready for action. The Dragon ships with an unpopulated prototyping area and missing a pin header for the HVSP. For most people this means soldering on pin headers and a ZIF socket then jumpering between the various programming headers and the header for the socket. Tired of working with jumper wires, [Jussi] designed a small PCB to make the connections (original link in Finnish). Continue reading “AVR Dragon Wiring Alternative” →