ABSTRACT
This chapter introduces the Pentium processor, its instruction set, and the basic addressing modes. It aims to develop some basic assembly language (AL) coding skills. An assembler translates a source program from AL to object code. Because a machine opcode statement is always translated into one instruction, AL is referred to as machine language. The AL statement is case insensitive. For eight-bit multiply instruction, the eight-bit multiplier is pre-loaded in AL and the eight-bit multiplicand can be in an 8-bit data register or in memory. The Pentium processor, also called the Intel architecture-32 (IA-32) bits supports two-address instructions in general. The IA-32 real mode means that the data register is 32 bits but the offset is still 16 bits so the segment size is 64 KB. When the processor operates in IA-16 or IA-32 real mode, the segment register contains a base address pointing to the segment.
