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Project:SpeedAdjustableBikeLight: Difference between revisions
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Simplify (only last 3 strings) and no V doubler. | Simplify (only last 3 strings) and no V doubler. | ||
This fits in the attiny85 pinout. | This just fits in the attiny85 pinout - but the attiny84 has more scope and flexibility. | ||
New link [http://www.mikrocontroller.net/attachment/14850/BikeLight.pdf on impedance matching and MCU control] of bike lights :). I am not sure what this means for my circuit and plans. | New link [http://www.mikrocontroller.net/attachment/14850/BikeLight.pdf on impedance matching and MCU control] of bike lights :). I am not sure what this means for my circuit and plans. | ||
Now using attiny84 - added | |||
# fourth mosfet (for another LED string) | |||
# voltage sense (to control pulsing of LED strings when there is insufficient power) | |||
# light sensor | |||
# JTAG debugging | |||
# Chip Select for possible communications via SPI. | |||
Another consideration is that SPI or TWI might be enough to to talk to other devices e.g. USB, ZigBEE, GPS or whatever. And the SPI/TWI pins are all on the clasic JTAG header, which is a luxury the attiny85 can not support. | |||
Ongoing... | Ongoing... | ||
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* Have the boards made.. | * Have the boards made.. | ||
Plan to make a heat pipe and sink combo. Starting with a copper tube long enough to mount across the handle bars. Flatten spots in the tube to mate with the LED aluminium carrier boards at angles that get the LED light pointed on the road, not in drivers eyes. | |||
Add water and heat it up so it boils, and seal it while filled with steam. The steam will condense to form a partial vacumn. Sounds so simple! | |||
Start software development. | Start software development... the easy bit. | ||
==Indicator LED== | ==Indicator LED== | ||
