The Intel 8089 input/output coprocessor was available for use with the 8086/8088 central processor. It was announced in May 1979, but the price was not available at that time.Intel Corporation, "Microcomputer Components: Intel Introduces the 8089 IOP, an I/O processor for the advanced 8088/8086 CPU family, the first of a series of new subsystem components", Intel Preview, May/June 1979, p. 7. It used the same programming technique as 8087 for input/output operations, such as transfer of data from memory to a peripheral device, and so reducing the load on the CPU. This I/O processor was available in July 1979 for US$194.20 in quantities of 100 or more.Intel Corporation, "8089 Price Announcement", Intel Preview, July/August 1979, p. 25. Intel second sourced this coprocessor to Fujitsu Limited.Intel Corporation, "NewsBits: Second Source News", Solutions, January/February 1985, P. 1
Because IBM didn't use it in the IBM PC design, it did not become well known; later Intel I/O coprocessors did not keep the x89 designation the way math coprocessors kept the x87 designation. It was used in the Apricot PC and the Intel Multibus iSBC-215 Hard disk drive controller. It was also used in the Altos 586 multi-user computer. Intel themselves used the 8089 in their reference designs (which they also commercialized) as System 86.
Peripherals Intel 8282/8283: 8-bit latch Intel 8284: clock generator Intel 8286 / 8287 were 8-bit data bus transceivers. Both Intel I8286 and I8287(inverting version) were available for US$16.25 in quantities of 100. Intel 8288: bus controller Intel 8289: bus arbiter
Literature and datasheets
8089 Assembler Users Guide; Intel 1979 8089 8 & 16-Bit HMOS I/O Processor; Intel 1980 John Atwood, Dave Ferguson: Debugging Strategies And Considerations For 8089 Systems , Application Note (AP-50), September 1979, Intel Corporation. Jim Nadir: Designing 8086, 8088, 8089 Multiprocessing System With The 8289 Bus Arbiter , Application Note (AP-51), März 1979, Intel Corporation. Robin Jigour: Prototyping with the 8089 I/O Processor, Application Note (AP-89), Mai 1980, Order number AFN 01153A, Intel Corporation. Hard Disk Controller Design Using the 8089, Application Note (AP-122), Order number 210202-001, Intel Corporation. Graphic CRT Design Using the Intel 8089, Application Note (AP-123), Intel Corporation.
References