The Intel 8087, announced in 1980, was the first floating-point coprocessor for the 8086 line of microprocessors.[5][6][7] The purpose of the chip was to speed up floating-point arithmetic operations, such as addition, subtraction, multiplication, division, and square root. It also computes transcendental functions such as exponential, logarithmic or trigonometric calculations. The performance enhancements were from approximately 20% to over 500%, depending on the specific application. The 8087 could perform about 50,000 FLOPS[6] using around 2.4 watts.[7]
Intel 8087 die
The 8087 was an advanced integrated circuit, pushing the limits of manufacturing technology of the period.[citation needed] Basic operations on the 8087 such as addition and subtraction can take over 100 machine cycles to execute and some instructions exceed 1000 cycles.[8] The chip lacks a hardware multiplier and implements calculations using the CORDIC algorithm.[9]
Sales of the 8087 received a significant boost when a coprocessor socket was included on the 1981 IBM PC motherboard. Development of the 8087 led to the IEEE 754-1985 standard for floating-point arithmetic. The available speed version were 4.77 (5), 8, and 10 MHz.[10] There were later x87 coprocessors for the 80186, 80286, 80386, and 80386SX processors. Starting with the 80486, the later Intel x86 processors did not use a separate floating-point coprocessor; floating-point functions were integrated with the processor.
Intel 80186 and its associated products were discontinued on March 30, 2007 for orders and September 28, 2007 for shipments.[11]
^"Product Change Notification" (PDF). 2 May 2006. Archived from the original (PDF) on 9 October 2006.
^Shvets, Gennadiy (8 October 2011). "IBM 8087 floating-point unit". CPU World. Retrieved 1 December 2011.
^Shvets, Gennadiy (8 October 2011). "AMD 8087 floating-point unit". CPU World. Retrieved 1 December 2011.
^Shvets, Gennadiy (8 October 2011). "Cyrix 8087 floating-point unit". CPU World. Retrieved 1 December 2011.
^Palmer, John F. (1980). "The INTEL® 8087 Numeric Data Processor" (PDF). AFIPS '80, Proceedings of the, May 19–22, 1980, National Computer Conference. Anaheim, California: ACM. pp. 887–893. doi:10.1145/1500518.1500674.
^ ab"8087". Coprocessor Dot Info. 2007. Archived from the original on 30 September 2011. Retrieved 1 December 2011.
^ ab"Intel FPU". cpu-collection.de. 2011. Retrieved 1 December 2011.
^Cite error: The named reference datasheet was invoked but never defined (see the help page).
^Shirriff, Ken (May 2020). "Extracting ROM constants from the 8087 math coprocessor's die". righto.com. Self-published by Ken Shirriff. Retrieved 3 September 2020. The ROM contains 16 arctangent values, the arctans of 2−n. It also contains 14 log values, the base-2 logs of (1+2−n). These may seem like unusual values, but they are used in an efficient algorithm called CORDIC, which was invented in 1958.
^Yoshida, Stacy, "Math Coprocessors: Keeping Your Computer Up for the Count", Intel Corporation, Microcomputer Solutions, September/October 1990, page 16
^"Product Change Notification" (PDF). 2 May 2006. Archived from the original (PDF) on 9 October 2006.
The Intel8087, announced in 1980, was the first floating-point coprocessor for the 8086 line of microprocessors. The purpose of the chip was to speed...
coprocessors). The 8087 was the first math coprocessor for 16-bit processors designed by Intel. It was built to be paired with the Intel 8088 or 8086 microprocessors...
performance. The Intel8087 was the standard math coprocessor for the 8086 and 8088, operating on 80-bit numbers. Manufacturers like Cyrix (8087-compatible)...
quantities of 100. Intel 8288: bus controller Intel 8289: bus arbiter Intel8087: Math Co-Processor x86 architecture IBM Personal Computer Motorola 68008...
of the years 87 BC, AD 87, 1987, 2087, etc. Atomic number 87, francium Intel8087, a floating-point coprocessor 87; Common gasoline rating 87 Sylvia, a...
such as the AMD 9511, Intel 8231/8232 and Weitek FPUs were treated as peripheral devices, while others such as the Intel8087, Motorola 68881 and National...
for the 8087 and 80287, but then omitted from later manuals until the October 2017 update of the Intel SDM. They are present on all known Intel x87 FPUs...
gradual underflow is used. Subnormal numbers were implemented in the Intel8087 while the IEEE 754 standard was being written. They were by far the most...
competitive asset. In 1984, Commodore signed a deal with Intel to second source manufacture the Intel 8088 CPU used in the IBM PC, along with a license to...
The Intel 80186, also known as the iAPX 186, or just 186, is a microprocessor and microcontroller introduced in 1982. It was based on the Intel 8086 and...
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In marketing, iAPX (Intel Advanced Performance Architecture) was a short lived designation used for several Intel microprocessors, including some 8086...
system-level prefix. An 8086 system, including coprocessors such as 8087 and 8089, and simpler Intel-specific system chips, was thereby described as an iAPX 86...
Name MDK-186 Manufacturer Intel Type Design Kit Microcomputer Origin US Keyboard None CPU Intel 80186 Coprocessor Intel8087 Documentation Technical Information:...
management. The 16-bit Intel x86 processors up to and including the 80386 do not include floating-point units (FPUs). Intel introduced the 8087, 80187, 80287 and...
extended precision format is an 80 bit format first implemented in the Intel8087 math coprocessor and is supported by all processors that are based on...
Similarly to the original IBM PC, the XT main board included a socket for the Intel8087 floating point arithmetic coprocessor. This optional chip, when installed...
1 MB of memory. The V20 was reported to have been compatible with the Intel8087 floating-point unit (FPU) coprocessor. NEC also designed their own FPU...
The Intel 8288 is a bus controller designed for Intel 8086/8087/8088/8089. The chip is supplied in 20-pin DIP package. The 8086 (and 8088) operate in...
are quite the opposite. In 1977 those features were designed into the Intel8087 to serve the widest possible market... Error-analysis tells us how to...
The Intel 8284 is a clock oscillator chip developed primarily for supplying clock signals for the Intel-8086/8087/8088/8089 series of processors. The...
important than speed. CORDIC has been implemented in the ARM-based STM32G4, Intel8087, 80287, 80387 up to the 80486 coprocessor series as well as in the Motorola...
bugs, scans expansion cards for bootable ROMs, and adds a socket for an Intel8087 math coprocessor. The original Tandy 1000 (and many other models), like...
trackball cable (later models used IR). It used an Intel 8086 processor running at 4.77 MHz. A 8087 math co-processor was optional. The amount of memory...
Voyager series and wrote part of their intermediate and advanced manuals. Intel8087 "IEEE Emanuel R. Piore Award Recipients" (PDF). IEEE. Archived from the...
The Intel 8289 is a Bus arbiter designed for Intel 8086/8087/8088/8089. The chip is supplied in 20-pin DIP package. The 8086 (and 8088) operate in maximum...
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