Hands-On RTOS with Microcontrollers

Power efficiency  

It may sound simple, but a fairly good way of making sure something draws less power is to turn it off (don't laugh—this can be surprisingly complicated depending on the parts involved, thanks to various leakage currents!). If complex MCUs with dozens of peripherals have any hope of being power efficient, there needs to be a way to turn off whatever functionality isn't required to minimize wasted power. This is typically accomplished by shutting off clocks to peripherals that aren't in use and ensuring that CMOS-based I/O pins are not floating (remember, it's the transitions in CMOS devices that draw the most power).

Another spec that is commonly found in datasheets is how much power is consumed per MHz of CPU clock—generally ...