寄存器中 置位 與 清除 -- C

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第3位的置位與清除操作。

#include <stdio.h>#include <stdlib.h>#include <string.h>#define BIT3 (0x1<<3)intmain(){int a = 0x00000000;printf("a = 0x%08X\n", a);/*置位第3bita = a | (0x1<<3)a = a | 0x8*/a |= BIT3;printf("a = 0x%08X\n", a);/*清楚第3bita = a & ~ (0x1<<3)a = a & ~ 0x8a = a & 0xfffffff7*/a &= ~BIT3;//printf("a = 0x%08X\n", a);}/*[[email protected] test_class]# gcc quote.cpp ;./a.outa = 0x00000000a = 0x00000008a = 0x00000000*/