type c pin定义

Given a PIN (value in HEX) and bit number, we have to SET and then CLEAR given bit of the PIN (val) by using Macros.

给定一个PIN(十六进制值)和位数，我们必须使用宏将SET(设置)，然后清除给定的PIN(值)位(值)。

Macros definitions:

宏定义：

    #define SET(PIN,N) (PIN |=  (1<<N))
#define CLR(PIN,N) (PIN &= ~(1<<N))

Here,

这里，

• SET and CLR are the Macro names

  SET和CLR是宏名称

• PIN is the value whose bit to set or/and clear

  PIN是要设置或清除的位的值

• N is the bit number to set or/and clear

  N是要设置或清除的位数

Example:

例：

#include <stdio.h>
#define SET(PIN,N) (PIN |=  (1<<N))
#define CLR(PIN,N) (PIN &= ~(1<<N))
int main(){unsigned char val = 0x11;
unsigned char bit = 2;
printf("val = %X\n",val);
//set  bit 2 of val
SET(val,bit);
printf("Aftre setting  bit %d, val = %X\n", bit, val);
//clear bit 2 of val
CLR(val,bit);
printf("Aftre clearing bit %d, val = %X\n", bit, val);
return 0;
}

Output

输出量

    val = 11
Aftre setting  bit 2, val = 15
Aftre clearing bit 2, val = 11

Explanation:

说明：

• Initially val is 0x11, its binary value is "0001 0001".

  最初val为0x11 ，其二进制值为“ 0001 0001” 。

• In the example, we are setting and clear bit 2 (please note start counting bits from 0 i.e. first bit is 0, second bit is 1 and third bit is 2).

  在该示例中，我们正在设置并清除位2(请注意从0开始计数位，即第一位为0，第二位为1，第三位为2)。

• After calling Macro SET(val,bit), the bit number 2 (i.e. third bit) will be set/hight and the value of val will be "0001 0101" that will be 0x15 in Hexadecimal.

  调用Macro SET(val，bit)后 ，将设置2位(即第三位)/高，并且val的值将为“ 0001 0101” ，十六进制为0x15 。

• And then, we are calling CLR(val,bit), after calling this Macro, the bit number 2 (i.e. third bit) will be cleared and the value of val will be "0001 0001" again, that is 0x11 in Hexadecimal.

  然后，我们调用CLR(val，bit) ，在调用此宏后，将清除位数2(即第三位)，并且val的值将再次为“ 0001 0001” ，即十六进制为0x11 。

翻译自: https://www.includehelp.com/c-programs/define-macros-to-set-and-clear-bit-of-a-pin-in-c.aspx

type c pin定义