Intel 80486SL

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80486SL KL Intel 486SL.jpg

The Intel's i486SL is the power-saving variant of the i486DX microprocessor. The SL was designed for use in mobile computers. It was produced between November 1992 and June 1993. Clock speeds available were 20, 25 and 33 MHz. The i486SL contained all features of the i486DX.

Intel American semiconductor company

Intel Corporation is an American multinational corporation and technology company headquartered in Santa Clara, California, in the Silicon Valley. It is the world's second largest and second highest valued semiconductor chip manufacturer based on revenue after being overtaken by Samsung, and is the inventor of the x86 series of microprocessors, the processors found in most personal computers (PCs). Intel ranked No. 46 in the 2018 Fortune 500 list of the largest United States corporations by total revenue.

Microprocessor computer processor contained on an integrated-circuit chip

A microprocessor is a computer processor that incorporates the functions of a central processing unit on a single integrated circuit (IC), or at most a few integrated circuits. The microprocessor is a multipurpose, clock driven, register based, digital integrated circuit that accepts binary data as input, processes it according to instructions stored in its memory, and provides results as output. Microprocessors contain both combinational logic and sequential digital logic. Microprocessors operate on numbers and symbols represented in the binary number system.

In addition, the System Management Mode (SMM) (the same mode introduced with i386SL) was included with this processor. The system management mode makes it possible to shut down the processor without losing data. To achieve this, the processor state is saved in an area of static RAM (SMRAM).

System Management Mode is an operating mode of x86 central processor units (CPUs) in which all normal execution, including the operating system, is suspended. An alternate software system which usually resides in the computer's firmware, or a hardware-assisted debugger, is then executed with high privileges.

In mid-1993, Intel incorporated the SMM feature and all other features in the 486SL in all its new 80486 processors and discontinued the SL series.

Refer to the respective section of the list of Intel microprocessors for technical details.

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