The 8086 Microprocessor- Internal Architecture
The Intel 8086 is a 16-bit microprocessor intended to be used as the CPU in a microcomputer. The term “16-bit” means that its arithmetic logic unit, internal registers, and most of its instructions are designed to work 16-bit binary words. It has 16-bit data bus and 20-bit address bus.
Words will be stored in two consecutive memory locations. If the first byte of a word is at an even address, the 8086 can read the entire word in one operation. If the first byte of the word is at an odd address, the 8086 will read the first byte in one operation, and the second byte in another operation.
Following figure shows the internal block diagram of 8086 microprocessor.
Fig. 8086 internal block diagram.
The 8086 CPU is divided into two independent functional parts, the bus interface unit or BIU, and the execution unit or EU.