The keyboard is the primary human interface tool in almost all industrial, commercial and consumer electronic products. The keyboard controller is used, not only to read devices which look like keyboards as in phones, microwave ovens, calculators, computers, oscilloscopes, wrist watches, TV and AC remotes, etc, but also operator consoles in large power plants and machines in factories, which do not look like keyboards. The switches in these consoles and keyboards are connected in a matrix and are read by a keyboard controller.

        Course-A1. Introduction to VHDL and VLSI design (I)

CONTENTS

        1. Schematic of keyboard matrix.
        2. Frequency divider for scanning and timing.
        3. Time Division Multiplexed (TDM) scanning of the matrix columns.
        4. Row encoder.
        5. Scan code generation. such as log2( ), etc.
        6. Interfacing logic for 8/16 bit CPUs.