22. Early x86 Processor Family

• Intel introduced microprocessors in 1969: 4-bit microprocessor 4004.

• 8-bit microprocessors are 8080 and 8085 models.

• 16-bit processors:

  • 8086 introduced in 1979.

  • 20-bit address bus, 16-bit data bus.

    • (8088 is a less expensive version.)

  • Uses 8-bit data bus.

  • Can address up to 4 segments of 64 KB.

  • Referred to as the real mode addressing.

  • Still fully compatible with modern x86 chips.