I decided to rebuild the Trippy RGB Light with a single RGB LED instead of three individual LEDs. I also changed from a 3 Volt supply to a 4.5 Volt supply. As a result I also had to change the resistor values (Blue - 150 Ohm, Red & Green - 270 Ohm). The video shows a marked improvement over the previous version.
This is another project that modifies the MiniPOV kit, similar to the LED Cube project I did previously. This time, instead of an LED matrix, one Red, one Green, and one Blue LED are used to create a multi-color light show by utilizing pulse-width modulation of the AVR's output. The construction is very similar to the LED Cube in that I also built the RGB from scratch. I did not, however, include an ISP header this time around because I felt the original program was adequate for a project of this scale. If I later decide to rebuild this project using multiple better quality LEDs I will definitely include an ISP header to be able to reprogram the RGB for other light shows.
In order to program the RGB Light I had to modify the makefile code for use with my USBTiny ISP in the same manner I did in the LED Cube project. This project is very simple to build and it produces an interesting light show. With some better quality LEDs with more diffuse viewing angles this could be even better. I will most likely rebuild this at some point in the future with more appropriate LEDs. Check out the video of my Trippy RGB Light in action (with a plastic bag between the RGB Light and the camera to diffuse the light for better color mixing).
This is another project I found via the Make Magazine Podcast. It is very simple to build, especially if you do what the original project recommends and start with the MiniPOV kit. Just follow the podcast's directions and modify the kit to get up and running. I took a somewhat different route. Since the MiniPOV is based off of an Atmel AVR 2313 microcontroller, and I have several of these chips and an AVR programmer, I built the project from scratch and modified it to use the AVR's in-system-programming (ISP) capability instead of a serial port like the MiniPOV. Otherwise my hardware ended up identical to the original.
On the software end I had to make some changes to the code from the project's ZIP file. I modified makefile to look for my USBTiny ISP instead of a serial port. Then all I had to do was follow the remainder of the podcast's instructions to compile, build and program the AVR. To make different LED animations all that is required is modify the LED code matrix in the ledcube.c file to make different LED configurations light up for different amounts of time. Check out the video of one of my animations. Definitely a fun, easy project.
As you can probably tell from my last couple of posts I have been getting into projects involving microcontrollers. While the GPS receiver I built used a PIC, many projects use an AVR instead. Made by Atmel, they are a direct competitor to the PIC. For a good comparison of the two check out this article. One of the more unique differences is that AVRs allow for in-circuit-programming. This means that you can plug the programmer into a header-pin assembly in the AVRs circuit and reprogram the AVR without having to pull the chip out of the circuit like with a PIC.
After seeing several interesting projects using AVRs in the MAKE Blog, I decided it would be a good idea to make an AVR programmer. Just like with my PIC programmer I did not want to be tied to a serial port and I didn't want to have to spend too much. I did some investigating and found the USB Tiny ISP. It is offered as a kit (or you can build if from scratch) for $22. The kit goes together very easily; the directions on the website are well written and detailed. Mine is pictured above and so far it functions perfectly. AVR projects are now in my near future.
