Every time you are making some circuit or more complex system, you always do some testing to make sure that your electronic “baby” is working properly and you can expose it to publicity. Lets say you are constructing some kind of robot. Then typical list of testing task may be as follows:

Stability tests using various [...]

Mostly all microcontrollers have built in Brown-out detection (BOD) circuit, which monitors supply voltage level during operation. BOD circuit is nothing more than comparator, which compares supply voltage to a fixed trigger level.
If microcontroller doesn’t have On-Chip Brown-Out detector, then there can be external circuit used :

The circuit above illustrates the brown out detectors circuit. [...]

Measuring signal period is common problem in embedded systems. This can be measuring time between two events or measuring signal frequency f=1/T and so on.
Measuring of time interval or period is based on comparing of event time t with discrete time usually produced by timer. This usually is done by filling the event time t [...]

ASM language is a low level programming language. It takes tons of time to develop embedded programs. Now even 8 bit microcontrollers arent as smal as they were earlier. The program memories are climbing to megabyte(s). Program structure becoming more complicated because of bigger functionality demand. This is why it is better to use higher [...]