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Bargraph 101 LED display HDSP8820 and AVR
AT90S8515
Not really a schematic, but just my fast hand drawn sketch to keep memory of how it's all connected.
The HDSP-8820 has 10x10 muxed LEDS = 100 and then one extra "overload" LED so a total of 101 LED's are located inside this nice unit.
I simply used a piece of VERO board and a good old AVR i found in my drawer.
The crystal was selected by random, what was floating around on the table that day.
SMD mini melf resistors are nice ! and wire wrap with teflon, I love it..
One LED lit up, funny looking LED's I guess they measure 1.2 by 0.2 mm each.
Making a lightshow with one LED back-forward scroll was easy.
Taking a VIDEO CLIP of it is harder.. due to the fast LED speed and lame camera shutter times,
it looks 100 times more cool in real life, what can I say.
Later I want to use the serial port for input data, so I can use it to calibrate and test my ultra sound range sensor system for my robot
The program is written i C using the free GNU C WINAVR compiler, I wrote the source in a hurry, not intended to show anybody,
so don't look at it, it is a mess, but it works so far.