数字电位器max5483的程序，哪位大哥大姐能给我指导一下吗[优游青春]

楼主:优游青春 2007年7月22日10:14

数字电位器max5483的程序，哪位大哥大姐能给我指导一下吗？
我是用I/O口模拟来实现的，单片机为89C52，但是我发现数字电位器的输出端 W 根本没有数据输出，哪位大哥大姐能给指导一下，感激不尽！
#include   <reg52.h>
#include   <intrins.h>
#include   <absacc.h>
#define uchar unsigned char
#define uint  unsigned int
sbit  MAX5483_CS = P3^2;
sbit  MAX5483_SCLK = P1^6;
sbit  MAX5483_DIN  = P1^7;
//max5483
void max5483write(uchar direct,uchar data1,uchar data2);
void main()
{
   max5483write(0x00,0xf4,0x00);
}
void max5483write(uchar direct,uchar data1,uchar data2)
{
    uchar i;
    MAX5483_SCLK = 0;
    MAX5483_CS=0;
    for (i=0;i  <8;i++)    //上升沿写入命令
    {
       MAX5483_SCLK =0;
       MAX5483_DIN = (bit)(direct&0x80);
       direct = direct  <  <1;
       MAX5483_SCLK =1;
     }
    for (i=0;i  <8;i++)    //上升沿写入数据
    {
       MAX5483_SCLK =0;
       MAX5483_DIN = (bit)(data1&0x80);
       data1 = data1  <  <1;
       MAX5483_SCLK =1;
    }
    for (i=0;i  <8;i++)    //上升沿写入数据
    {
       MAX5483_SCLK =0;
       MAX5483_DIN = (bit)(data2&0x80);
       data2 = data2  <  <1;
       MAX5483_SCLK =1;
    }
    MAX5481_CS=1;
}