TAILIEUCHUNG - The 80x86 IBM PC and Compatible Computers- P16

The 80x86 IBM PC and Compatible Computers- P16: Praised by experts for its clarity and topical breadth, this visually appealing, one-stop source on PCs uses an easy-to-understand, step-by-step approach to teaching the fundamentals of 80x86 assembly language programming and PC architecture. Offering users a fun, hands-on learning experience, it uses the Debug utility to show what action the instruction performs, then provides a sample program to show its application. | SECTION MMX TECHNOLOGY In this section we discuss the MMX MultiMedia extension technology used in some of the Intel processors. DSP and multimedia To run high-quality multimedia applications with sound and graphics requires very fast and sophisticated mathematical operations. Such complex operations are normally performed by a highly specialized chip called DSP digital signal processing . DSP chips are the main engines performing tasks such as 2- and 3-D graphics video and audio compression fax modem PC-based telephoning with live pictures and image processing. There are three approaches to equip the PC with DSP capability. 1. Use a full-fledged DSP chip on the board along with the main CPU. This is the best and ideal approach since there are some very powerful DSP chips out there. However the problem is that there is no industry-wide standard to be followed by the PC designers and the lack of such a standard can lead to incompatibility both in hardware and software. 2. Use the x86 and x87 FP floating-point instructions to emulate the function of DSP. This is slow and performance is unacceptable. 3. The third approach is to incorporate some DSP functions into the x86 microprocessor. This approach leaves everyone at the mercy of Intel yet it brings compatibility and a unified approach to the issue. Although the performance is not as good as the first approach it is much better than the second approach. The third approach is exactly what happened. In early 1997 Intel introduced a series of Pentium and Pentium Pro chips with somewhat limited DSP capability called MMX technology . In the case of Intel s MMX technology software compatibility both on the BIOS and operating system levels was the most important goal. It needs to be noted that although MMX does not have a rich set of instructions normally associated with DSP chips such as Texas Instruments 320xxx it still performs many of the DSP functions reasonably well. Register aliasing by MMX As stated earlier one

Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.