The x86 Microprocessors: 8086 to Pentium, Multicores, Atom and the 8051 Microcontroller, 2nd Edition

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Programming Concepts—IV

IN THIS CHAPTER, YOU WILL LEARN

• The difference between peripheral I/O and memory mapped I/O.
• The use of the input/output instructions of 8086.
• The importance of modular programming.
• The use of directives which facilitate modular programming.
• To write programs in different modules and link them.
• To use assembly modules in a C programming environment.

Introduction

We know that the processor we use is connected to the I/O as well as the memory. So far, we have only dealt with data being read from and written to memory. We have accessed I/O devices like the keyboard and the video monitor, but for that we used DOS interrupts, which are functions already written and tested. Now, let us try to deal with I/O directly ...