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Tagged Image File Format  |  1997-06-18  |  104KB  |  692x438  |  16-bit (14,262 colors)
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OCR: Memory 20 100 B8 20101 01 mov ax,1 201 102 00 To 80286 201 103 BB 20 10 02 nOW bx,2 20105 00 The last byte Q mov ax and the first byte of mov bx,2 which together form word l-aligned word, are prefetched with single word- -sized access; the 80286 later splits the bytes apart internally in the prefetch quoue FIGURE 15.2 Normally it doesn't matter whether instructious are word aligned or not, because the 80286 fetches instructions into the prefetch queue one -aligned word it time, then internally separates the bytes in the prefetch queue O[1 an as needed basis 20104 asingle prefotch preferch pspsatr