List of Intel Microprocessors - The 16-bit Processors: MCS-86 Family

The 16-bit Processors: MCS-86 Family

• 8086
  • Introduced June 8, 1978
  • Clock rates:
    • 5 MHz with 0.33 MIPS
    • 8 MHz with 0.66 MIPS
    • 10 MHz with 0.75 MIPS
  • The memory is divided into odd and even banks; it accesses both banks concurrently to read 16 bits of data in one clock cycle
  • Bus Width 16 bits data, 20 bits address
  • Number of Transistors 29,000 at 3 µm
  • Addressable memory 1 megabyte
  • Up to 10X the performance of 8080
  • Used in portable computing, and in the IBM PS/2 Model 25 and Model 30. Also used in the AT&T PC6300 / Olivetti M24, a popular IBM PC-compatible (predating the IBM PS/2 line.)
  • Used segment registers to access more than 64 KB of data at once, which many programmers complained made their work excessively difficult.

• 8088
  • Introduced June 1, 1979
  • Clock rates:
    • 5 MHz with 0.33 MIPS
    • 8 MHz with 0.75 MIPS
  • Internal architecture 16 bits
  • External bus Width 8 bits data, 20 bits address
  • Number of Transistors 29,000 at 3 µm
  • Addressable memory 1 megabyte
  • Identical to 8086 except for its 8 bit external bus (hence an 8 instead of a 6 at the end)
  • Used in IBM PCs and PC clones

• 80186
  • Introduced 1982
  • Clock rates
    • 6 MHz with > 1 MIPS
  • Number of Transistors 29,000 at 2 µm
  • Included two timers, a DMA controller, and an interrupt controller on the chip in addition to the processor (These were at fixed addresses which differed from the IBM PC, making it impossible to build a 100% PC-compatible computer around the 80186.)
  • Added a few opcodes and exceptions to the 8086 design; otherwise identical instruction set to 8086 and 8088.
  • Used mostly in embedded applications – controllers, point-of-sale systems, terminals, and the like
  • Used in several non-PC-Compatible MS-DOS computers including RM Nimbus, Tandy 2000, and CP/M 86 Televideo PM16 server
  • Later renamed the iAPX 186

• 80188
  • A version of the 80186 with an 8-bit external data bus
  • Later renamed the iAPX 188

• 80286
  • Introduced February 1, 1982
  • Clock rates:
    • 6 MHz with 0.9 MIPS
    • 8 MHz, 10 MHz with 1.5 MIPS
    • 12.5 MHz with 2.66 MIPS
    • 16 MHz, 20 MHz and 25 MHz available.
  • Bus Width: 16 bit data, 24 bit address.
  • Included memory protection hardware to support multitasking operating systems with per-process address space
  • Number of Transistors 134,000 at 1.5 µm
  • Addressable memory 16 MB (16 MB)
  • Added protected-mode features to 8086 with essentially the same instruction set
  • 3-6X the performance of the 8086
  • Widely used in IBM-PC AT and AT clones contemporary to it