====== universal stepper motor controller ======

after doing some datasheet reading and experiments with [[http://www.atmel.com/dyn/resources/prod_documents/doc2535.pdf|ATiny13]] uC [[:prjs:usmc:usmc|universal stepper motor controller]] has finally grown up enough to show it! :) final version uses [[http://www.atmel.com/atmel/acrobat/doc0368.pdf|AT89C2051]] uC, uses interrupts and enters idle mode often, in order to minimize power consumption. it supports both unipolar and bipolar stepper motors, has step-by-step mode along with continuous (aka: "turbo") mode of operations.