led on Bald Engineer

DCA Pro Transistor Tester Review | Workbench Wednesdays

Wed, 07 Aug 2019 14:19:09 +0000

When it comes to transistors, there are only so many things a multimeter can measure. The DCA Pro from PEAK Electronics makes short work of testing parts like a transistor. This small device can determine pinout, component type, and essential parameters in a matter of seconds. Not only that but it can be connected to a (Windows) PC and draw parameter curves. Check out the video review to see how the device and software work. Then head over to the element14 page where you can download a zip file full of example parts I measured for you. Use the free DCA Pro software to open them.

Watch this video on YouTube

Proper Larson Scanner with Software PWM (Repost)

Wed, 21 Oct 2015 16:00:03 +0000

Last week I had a detailed Arduino tutorial on software pulse width modulation using millis() and micros(). Why? Because I wanted to create a Proper Larson Scanner, with persistence and at least 8 LEDs. KITT larson scanner example Even though it is a popular project for the Arduino Uno, most Larson scanner tutorials, like my first one, have a few flaws. First, there is no persistence, or tail, to the LED as it moves back and forth. Persistence could be solved by using pulse-width-modulation. The Uno and other 328p-based micros only have 6 Pulse Width Modulation (PWM) pins. And let’s be honest, every project is made better by adding more LEDs. :)

Arduino Software PWM with millis()

Wed, 07 Oct 2015 13:00:04 +0000

The Arduino Uno has six pins dedicated to Pulse Width Modulation (PWM). PWM is great for analog-like control for the speed of motors or LED fading. But what if you want to control more than 6 devices? Or what if you’re using the PWM pins to control servo motors, but still want to fade an LED on a 7th pin? One option is to change boards and processors. For example, you could move up to the Arduino Mega 2560. That means a bigger board and more cost.

Pushbutton and Flashing LED tutorial with millis()

Wed, 06 May 2015 14:00:21 +0000

How to blink (or flash) a LED without delay() and detect button pushes One of the limitations of the delay() function is that nothing else can really be done. This presents a problem when you want to flash a LED while waiting for a pushbutton to be pressed. Flashing the LED with millis() and using a flag variable to find if the LED should be flashing solves this problem. Consider this another example to my virtual millis() cookbook.

Arduino: Chasing LEDs with millis()

Thu, 12 Dec 2013 12:00:34 +0000

A popular LED project is the “Larson Scanner.” This scanner emulates the effect seen on KIT from Knight Rider and the Cylons in Battlestar Galactica. The code is usually written using “delay()” which means you can’t combine it with anything else. The following code could be put into a function, called periodically and allow your code to scan while doing other things. One thing to note, a proper Larson Scanner has some persistence to the next and previous LEDs, this code does not. Maybe that would be a good exercise for the reader?

LED Matrix Arduino Shield

Sat, 06 Oct 2012 16:28:07 +0000

Status: Completed GitHub: https://github.com/baldengineer/8x6-LED-Matrix-Shield Abstract After getting a couple of flashing lights working on a microprocessor, the next fun project is generally building some kind of Matrix. At first I built a 5x5 LED matrix which was relatively simple to solder together. When trying to make one much larger, the task because significantly more complex. That’s when I decided to build a LED Matrix Shield for the Arduino which did not use Charliplexing, like the LoL shield. I wanted something that was simpler to understand and (ultimately) code for. Unfortunately, 5mm LEDs means 8 columns x 6 rows, instead of the traditional 8x8.

BinBoo: Building the front panel LEDs

Sun, 15 Jul 2012 16:14:06 +0000

Short build-lapse video of building up the front panel “matrix” used in BinBoo. This isn’t a true LED matrix. Instead it combining all of the LEDs into a common Anode, since the Cathodes are all controlled by individual outputs of the TLC5940. I decided to wire up 16 LEDs, even though a binary clock only needs 11 or 12. This gives some flexibility to other uses for the box, like a random sci-fi computer pattern.

Binary + Bamboo = BinBoo

Sun, 20 May 2012 00:22:14 +0000

Several months ago I started a project to build a Binary Clock, using a Laser Cut enclosure. The plan was to use Ponoko’s laser cutting service. Looking through the materials available, I decided to use Bamboo. Knowing I was going to build a Bamboo enclosure for a Binary clock, helped me come to the name BinBoo. Even though I call it a Binary Clock, it is actually a BCD clock…

millis() Tutorial: Arduino Multitasking

Fri, 07 Jan 2011 04:01:55 +0000

After working through these exercises, check out this article on how to avoid rollover or reset mills(). After learning how to flash a single LED on your Arduino, you are probably looking for a way to make cool patterns, but feel limited by the use of delay(). If you ask in the forums, you get told to look at the “Blink Without Delay” example. This example introduces the idea of replacing delay() with a state machine. If you’re confused how to use it, this tutorial is setup to take you from blinking two LEDs with delay, to using an alternate method, right down to how you can use millis().

TLC5940 Painter PCB

Sun, 05 Apr 2009 19:11:09 +0000

TLC5940NT Painter Board This screen shot is an all-layer view of my TLC5940 painter board. The 1st draft featured two TLC5940s, but I decided it made the board too large. Instead, I wanted the ability to mount the painter boards around the LED’s shadow box. This should make routing all the wires much easier. The board is approximately 1.25in x 3.5in. All signals have been routed on the top or bottom layers. Most of the components will mount on (or through) the top layer. Some coupling caps have been put on the bottom. Initially the board had a 7805 built in, to provide +5V to the painter boards and the arduino. Instead, I ripped that out and plan to use the regulator on the arduino instead. There are 6 data and power ports. SER-IN will either come from the host arduino, or from another painter board. SER-OUT contains 2 less pins than SER-IN. I included two surface mount buttons in the layout, so I could get some inputs back to the Arduino, these are entirely option and will only work on a single board.

Row Your Boat, Part 1

Thu, 26 Mar 2009 02:28:39 +0000

This pattern is called Row Your Boat. As one of the strips starts to get brighter, a nearby strip will join in the fading. After completing a fade cycle, they start switching colors. There is a random strobe thrown in there as well. The first 10 seconds are with a diffuser (piece of paper), the last 10 seconds are without. The final panel will use a diffuser. The colors have no correction yet, so red is really dim and green is really bright. It looks like one of the channels of my TLC5940 is going bad. The center LED strip’s blue is very dim. I’m not going to look much into it right now though. Instead, I will wait until I fab a PCB for the 5940 (this weekend?)