Intel 8089

Lore & Background

The Intel 8089 employed the same programming technique as the 8087 coprocessor for input/output operations. It was not used in the IBM PC design, which contributed to its lack of widespread recognition. Later Intel I/O coprocessors did not retain the x89 designation, unlike math coprocessors which kept the x87 designation. The 8089 found use in the Apricot PC, the Intel Multibus iSBC-215 hard disk drive controller, and the Altos 586 multi-user computer. Intel themselves incorporated the 8089 into their reference designs, which they also commercialized as the System 86. Intel second sourced this coprocessor to Fujitsu Limited.

Reader's Guide

The Intel 8089's significance lies in its role as an early I/O coprocessor that offloaded data transfer tasks from the main CPU, a concept that would become more common in later systems. Its lack of adoption in the IBM PC limited its market exposure and historical prominence. The 8089 was used in several commercial products, including the Apricot PC, the Intel Multibus iSBC-215 hard disk drive controller, and the Altos 586 multi-user computer. Intel also used it in their own System 86 reference designs. The coprocessor was supported by a range of Intel peripheral chips, such as the 8282/8283 8-bit latch, the 8284 clock generator, the 8286/8287 data bus transceivers, the 8288 bus controller, and the 8289 bus arbiter. A body of literature, including an assembler user's guide and several application notes, was published by Intel to assist developers. The 8089's legacy is that of a capable but niche component, overshadowed by the success of the x87 math coprocessor series.

Did You Know?

• The Intel 8089 was announced in May 1979, but its price was not available at that time.
• It was available in July 1979 for US$194.20 in quantities of 100 or more.
• Intel second sourced the 8089 to Fujitsu Limited.
• The 8089 was used in the Apricot PC and the Intel Multibus iSBC-215 hard disk drive controller.