Embedded Systems Design, 2nd Edition

Basic peripherals 131

4 Basic peripherals

This chapter describes the basic peripherals that most

microcontrollers provide. It covers parallel ports which are the

simplest I/O devices, timer counters for generating and measur-

ing time- and count-based events, serial interfaces and DMA

controllers.

Parallel ports

Parallel ports provide the ability to input or output binary

data with a single bit allocated to each pin within the port. They are

called parallel ports because the initial chips that provided this

support grouped several pins together to create a controllable data

port similar to that used for data and address buses. It transfers

multiple bits ...