softcopy of a transistor data-book.......?

If your microcontroller doesn’t have a digital-to-analog converter, you can make a passable replacement with nothing more than a pulse-width-modulated signal and a low-pass filter.

Understanding the relationship between resolution and accuracy will help you determine how small a voltage, current, or resistance—or how small a change in those values—that you can actually measure with your digital multimeter.

In this article we’ll discuss the design for a custom microcontroller programming/debug/extension PCB and we’ll look at an example project.