Once upon a time I spent some time comparing Intel & Motorola microcontrollers. The little ones were fairly simple, but the bigger ones got pretty complicated. The 68HC11 has a whole slew of options involving timers, so I made up this drawing to try and illustrate the relationships between all the various parts that were connected to the timer. I originally drew it by hand and colored it with highlighters. I got this image by scanning an old black & white Xerox that I found sitting in a notebook on my bookshelf. Back in the early 1980's we didn't have color copiers.
6 months ago