FOR THA NERDS!

Hi Nerds.

openVolver runs on a Atmel ATMega328 AVR 8-bit microcontroller. It feeds data into three Macroblock constant-current LED sink drivers. It uses two timer interrupts for 36 8-bit channels of software PWM and a FPS timer. It implements frame blending and two different overlay modes when it's running 2 or 3 patterns. All data is stored on a microSD card and we are using the FATFS library for pattern readback.

You can reprogram the piece with any 6-pin ISP AVR programmer. There is a 6-pin header for programming at the bottom of the PCB. Programming should be done from the back of the board.

The Eagle files are here: Schematic and Board.

Source and hex file are here. It was developed in AVR Studio 4.0 -- you will probably need to enter your own path to your /avr/include directory if you open it up in your version of AVR Studio. The hex file is /openvolver/default/openvolver.hex if you just need to reprogram your unit.

Here is the BOM -- if you do not have the SD card, you will not have the SD card holder.

All part numbers are Digikey unless specified. Other sources are Mouser and the swell folks at King Electronics. We get our LEDs from HB LED.

HACKS:

You can run the blinky off of any 9-12V power supply by soldering the wires into the + and - terminals on the back of the board, located between the battery connector and the mounting hole. The 7805 might get a little hot if you are running at 12V but it's within its spec.

You can fill the LED slots with any LED you want, as long as it does not pull more than 20mA. Using high-wattage LEDs will thermally kick the ass of the LED driver chips.

Got a hack? Email me at twina at imagenode.org to let me know...