Difference between revisions of "Walcott Visualization"
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==Hardware== | ==Hardware== | ||
− | The visualization uses a PIC to decode a 4E Network packet containing six 0-255 values. The packet should look something like: | + | The visualization uses a PIC 18F1220 to decode a 4E Network packet containing six 0-255 values. The packet should look something like: |
<pre> | <pre> | ||
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E | E | ||
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− | These values become the duty cycles of six software PWMs running in the main loop of the firmware. | + | These values become the duty cycles of six software PWMs running in the main loop of the firmware. The latest version of the firmware is available at [http://bemix.mit.edu/svn/fourtheast/browse/visualization/pic/ svn://bemix.mit.edu/var/svn/repos/visualization/pic]. |
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+ | The PWM outputs are fed into TIP110 power darlingtons through 1K base resistor. The power transistors are connected to a set of modified christmas lights in a common emitter configuration. Each TIP110 drives an array of 2 lights in series and n in parallel. The lights are powered from the +5V rail of a computer power supply. | ||
==Software== | ==Software== |
Revision as of 19:35, 3 July 2006
Contents
Overview
The Walcott visualization integrates a set of rewired christmas lights into the Bemix system. A custom XMMS plugin running on Cocoa Table calculates five 0-255 values based on Fourier transform of the music playing in the lounge. These numbers are wrapped into a 4E Network packet and sent to the serial port to a PIC microcontroller. The PIC parses the packet using BemixOS technology and sets the brightness of each color of light using PWM.
Hardware
The visualization uses a PIC 18F1220 to decode a 4E Network packet containing six 0-255 values. The packet should look something like:
\ H v (ignored) (ignored) (channel 1) (channel 2) (channel 3) (channel 4) (channel 5) (channel 6) \ E
These values become the duty cycles of six software PWMs running in the main loop of the firmware. The latest version of the firmware is available at svn://bemix.mit.edu/var/svn/repos/visualization/pic.
The PWM outputs are fed into TIP110 power darlingtons through 1K base resistor. The power transistors are connected to a set of modified christmas lights in a common emitter configuration. Each TIP110 drives an array of 2 lights in series and n in parallel. The lights are powered from the +5V rail of a computer power supply.