Microprocessor Essay Example | Topics and Well Written Essays - 1000 words

Microprocessor - Essay Example The 80286 contains a total of fourteen registers that are of interest to the application programmer. These registers may be grouped into four basic categories: General registers. These eight 16-bit general-purpose registers are used primarily to contain operands for arithmetic and logical operations. Segment registers. These four special-purpose registers determine, at any given time, which segments of memory are currently addressable. Status and Control registers. These three special-purpose registers are used to record and alter certain aspects of the 80286 processor state. For descriptive purposes, the 80286 instruction set is partitioned into three distinct subsets: the Basic Instruction Set, the Extended Instruction Set, and the System Control Instruction Set. The "hierarchy" of instruction sets defined by this partitioning helps to clarify the relationships between the various processors in the 8086 family . Five of the general- purpose registers are available for offset addres s calculations. These five registers, shown in figure 2-4, are SP, BP, BX, SI, and DI. SP is called a pointer register; BP and BX are called base registers; SI and DI are called index registers. The Basic Instruction Set, comprises the common subset of instructions found on all processors of the 8086 family. Included are instructions for logical and arithmetic operations, data movement, input/output, string manipulation, and transfer of control.... address lines, giving these processors one megabyte of addressability (2^20 = 1MB). The 80286, with its 24 address lines, gives 16 megabytes of addressability (2^24 = 16 MB). The 286 was designed to run multitasking applications, including communications (such as automated PBXs), real-time process control, and multi-user systems. The 80286 contains a total of fourteen registers that are of interest to the application programmer. These registers may be grouped into four basic categories: General registers. These eight 16-bit general-purpose registers are used primarily to contain operands for arithmetic and logical operations. Segment registers. These four special-purpose registers determine, at any given time, which segments of memory are currently addressable. Status and Control registers. These three special-purpose registers are used to record and alter certain aspects of the 80286 processor state. For descriptive purposes, the 80286 instruction set is partitioned into three distinct subsets: the Basic Instruction Set, the Extended Instruction Set, and the System Control Instruction Set. The "hierarchy" of instruction sets defined by this partitioning helps to clarify the relationships between the various processors in the 8086 family . Five of the general- purpose registers are available for offset address calculations. These five registers, shown in figure 2-4, are SP, BP, BX, SI, and DI. SP is called a pointer register; BP and BX are called base registers; SI and DI are called index registers. The Basic Instruction Set, comprises the common subset of instructions found on all processors of the 8086 family. Included are instructions for logical and arithmetic operations, data movement, input/output, string manipulation, and