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Four way bit switch using RC servo pulse input

The hardware is extremely simple ! here are four leds connected to all four outputs using 280 ohm resistors.

AVR microcontroller AtTiny45 is used.
Four outputs Active LOW, inactive outputs are floating,
so you can combine resistor networks to generate analog voltages if needed
for remote controlling cameras or whatever you need.

The servo pulse is filtered in software so it needs to be stable at least two cycles before updating the output states:
this makes it possible for you to pass "Signal B" in your way to "Signal A" without activating "Signal B".

Signal A = PB1 pin 6 (-70 to -199%)
Signal B = PB2 pin 7 (-20 to -50%)
Signal C = PB3 pin 2 (+20 to +50%)
Signal D = PB4 pin 3 (+70 to +199)
100% = center position 1.500mS servo pulse time.

four-way-bit-switch.wmv Function demonstration video clip 800kb
four-way-bit-switch-rc.wmv Demonstration using RC transmitter and switches video clip 460kb

four-way-t45bitsw4.zip Free HEX file download for the microcontroller, Active LOW version
four-way-t45bitsw4active-hi.zip Free HEX file, special ACTIVE HI output version,
this Active hi version can be used to directly drive N fets or other items needing active hi signal, no floating outputs when inactive in this version
Fuses: 8 MHz internal osc 64ms startup, no divide, Brown-out 2.7V (Reading fuses = 0xFF, 0xDD, 0xE2)

I had to delete the free HEX files, this project is sold to a distributor that plan to manufacture it and sell it

Made by: Thomas Scherrer, OZ2CPU, Feb 28th 2007