怎么用89C51控制74HC595

本程序是发送数据到595的子程序
#define DK PORTC
#define DATA PINC0 ////数据--------------74HC595 14#
#define ST PINC1 ////锁存时钟----------74HC595 12#
#define SH PINC2 ////移位时钟----------74HC595 11#

*/
//送出8位串行数据
void out_disp(unsigned char data)
{

unsigned char i;
for (i=0;i<8;i++)
{
cbi(DK,SH); ////拉低移位时钟
if (data&0x80) sbi(DK,DATA);

else cbi(DK,DATA);

data<<=1;
sbi(DK,SH); ////提高移位时钟
delay_us(1);
}

delay_us(1);

}