单片机程序中“s=-crol-(s,1)"是什么意思?有没和它类似大或相反的...

发布网友发布时间：2024-10-05 14:15

共3个回答

热心网友时间：2024-10-05 16:20

将S左移一位，起到乘二的作用，因为直接通过单片机来算乘除法会非常慢，因此用左移一位的方法来实现，同理_cror_(s,n)指s向右移n位

热心网友时间：2024-10-05 16:24

变量s左移一位，相当于：s = s * 2;
上面语句也可以写作: s *= 2。

相反的语句就是_cror_，右移。

热心网友时间：2024-10-05 16:21

#include <intrins.h>
unsigned char _crol_ (unsigned char c, /* character to rotate left */
unsigned char b); /* bit positions to rotate */
Description:
The _crol_ routine rotates the bit pattern for the character c left b bits. This routine is implemented as an intrinsic function. The code required is included in-line rather than being called.

Return Value:
The _crol_ routine returns the rotated value of c.

Attributes:
reentrant, intrinsic

See Also:
_cror_, _irol_, _iror_, _lrol_, _lror_

Example
#include <intrins.h>

void tst_crol (void) {
char a;
char b;

a = 0xA5;

b = _crol_(a,3); /* b now is 0x2D */

}