請參考下面程序:

// SPROM函數

/* +-------------+
  | SPROM開始位 |
  +-------------+ */
void start24(void)
{
SDA_24 = 1; CLK_24 = 1; nop(); SDA_24 = 0; nop();  CLK_24 = 0;
return;
}

/* +-------------+
  | SPROM停止位 |
  +-------------+ */
void stop24(void)
{
SDA_24 = 0; CLK_24 = 1; nop(); SDA_24 = 1;
return;
}

/* +---------------------+
  | 寫數據到SPROM數據線 |
  +---------------------+ */
void wd_24(char c)
{
unsigned char n;
for(n=0;n<8;n++)
{
 SDA_24 = 0x80 & c; c = ACC;    // 數據高位送SDA針并左移一位
 CLK_24 = 1; nop(); CLK_24 = 0; // 正時鐘脈沖周期
}
return;
}

/* +---------------+
  | SPROM ASK周期 |
  +---------------+ */
bit ack_24(void)
{
bit b;
SDA_24 = 1; CLK_24 = 1; b = SDA_24; CLK_24 = 0;
return(b);
}

/* +-------------+
  | SPROM字節寫 |
  +-------------+ */
void write24(char a, char d)
{
unsigned int i;
start24();
if(MTYPE){wd_24(0xa0); ack_24();}
else a=a<<1;
wd_24(a); ack_24();
wd_24(d); ack_24();
stop24();
i=0;
while(1)
{
 start24();
 wd_24(0xa0);
 if(ack_24()==0)break;
 if(i>8000)break;
 i++;
}
return;
}

/* +-------------+
  | SPROM字節讀 |
  +-------------+ */
char read24(char a)
{
unsigned char n;
char c;
c = 0;
start24();
if(MTYPE){wd_24(0xa0); ack_24();}
else {a=a<<1;a++;}
wd_24(a); ack_24();
if(MTYPE){start24(); wd_24(0xa1); ack_24();}
SDA_24 = 1;
for(n=0;n<8;n++)
{
 CLK_24 = 1;
 c = c<<1; if(SDA_24)c++;     // 讀相應位
 CLK_24 = 0;
}
ack_24(); stop24();
return(c);
}