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用的是创龙的OMAP-L138的板子和XDS100v3仿真器,用的方法是TSCL = 0;
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6 p& C6 h4 s* N0 X1 B unsigned long long start,stop,overhead;6 K$ L7 c& z7 `! i
start = _itoll(TSCH,TSCL);5 m1 J6 a {& b: I' A- K1 R+ m; h
stop = _itoll(TSCH,TSCL); 9 T/ @" o& T) q. o( [
% @8 E9 H4 P) p8 O* u: a' Joverhead = stop - start;
6 c Z7 X+ g" j+ G7 O& F/ `) aprintf("overhead run-time is %d\n",overhead);
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start = _itoll(TSCH,TSCL);4 R8 v) |3 q' j( f7 H( b
//here is function c* p3 Y3 F$ u! R
function();
/ t# v S. K6 b# Zstop = _itoll(TSCH,TSCL);' [) U) m1 v: r/ i! z1 P
printf("The function run-time time is %lu\n",(stop - start - overhead));
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+ k$ V2 e; K6 _ |/ M" L2 r" W为什么每次测量出来的时间都不一致?测量出来的不是一个固定的值。
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