__CONFIG(MCLRDIS & WDTDIS & EXTRC & PROTECT);

/*----------------------------------------------------
?Function : Delay??????????
?Input : unsigned int (counter)???????
?Output : None??????????
?Description : Delay routine???????
?if counter=1? delay 35us , if counter=10 delay 134us,
?if counter=100 delay 1.12ms,
?These delay is base on internal 4MHz?????
------------------------------------------------------*/?????
void Delay(unsigned int counter)
{
?? while(counter>0) counter--;?
}????????????????????????????????????

/*----------------------------------------------------
?Function : Pulse??????????
?Input : None???????
?Output : None??????????
?Description : Send a pulse (10) to Serial Data Clock(CLK)???????
------------------------------------------------------*/?????
void Pulse(void)
{
??? CLK = 1;
??? Delay(25);
??? CLK = 0;
}

/*----------------------------------------------------
?Function : StartBit??????????
?Input : None???????
?Output : None??????????
?Description :??
?1. Set Chip Select(CS) = 1 (high)
?2. Set a Start Bit(1) to Serial Data Input(DI)
------------------------------------------------------*/?????
void StartBit(void)
{
??? CS = 1;
??? DI = 1;
??? Pulse();
}

/*----------------------------------------------------
?Function : EWEN??????????
?Input : None???????
?Output : None??????????
?Description :? ERASE/WRITE Enable
?------------------------------------------------------*/?????
void EWEN(void)
{
??? unsigned char i,temp;

??? StartBit();????????????????? /* 1 */

??? temp = 0x80;??????????????????????? /* 0011xxxx ,(opcode:00, Address:11xxxx) */
??? for(i=0; i<8; i++) {
??????? if(0x30 & temp)
??????????? DI = 1;
??????? else
??????????? DI = 0;
??????? Pulse();
??????? temp >>= 1;
??? }

??? CS = 0;
}

/*----------------------------------------------------
?Function : EWDS??????????
?Input : None???????
?Output : None??????????
?Description :? ERASE/WRITE Disable
?------------------------------------------------------*/?????
void EWDS(void)
{
??? unsigned char i;

??? StartBit();????????????????? /* 1 */

??? DI = 0;?????????????????????? /* 0000xxxx, (opcode:00, Address:00xxxx) */
??? for(i=0; i<8; i++)
??????? Pulse();

??? CS = 0;
}

/*----------------------------------------------------
?Function : Write93LC46??????????
?Input : unsigned char Offset Address, unsigned int tx_data???????
?Output : None??????????
?Description :? Write 16bits data in to 93LC46 Offset Address
?------------------------------------------------------*/?????
void Write93LC46(unsigned char Offset_Addr, unsigned int tx_data)
{
??? unsigned char Addr, i;
??? unsigned int temp;

??? EWEN();

??? StartBit();????????????????? /* 1 */
??? Offset_Addr=Offset_Addr&0x3F; /* 6bits address */
??? Addr = Offset_Addr + 0x40;????????? /* 01AAAAAA ,(opcode:01, address:AAAAAA) */
??? temp = 0x0080;
??? for(i=0; i<8; i++) {
??????? if(Addr & temp)
??????????? DI = 1;
??????? else
??????????? DI = 0;
??????? Pulse();
??????? temp >>= 1;
??? }

??? temp = 0x8000;????????????????????? /* DDDDDDDDDDDDDDDD(16bits data)*/
??? for(i=0; i<16; i++) {
??????? if(tx_data & temp)
??????????? DI = 1;
??????? else
??????????? DI = 0;
??????? Pulse();
??????? temp >>= 1;
??? }
??? CS = 0;

??? EWDS();
}

/*----------------------------------------------------
?Function : Read93LC46??????????
?Input : unsigned char Offset Address
?Output : unsigned int??????????
?Description :? Read 16bits data from 93LC46 offset address
?------------------------------------------------------*/?????
unsigned int Read93LC46(unsigned char Offset_Addr)
{
??? unsigned char Addr, i, temp;
??? unsigned int? rx_data;

??? StartBit();?????????????????? /* 1 */
??? Offset_Addr = Offset_Addr&0x3F; /* 6bits address */
??? Addr = Offset_Addr + 0x80;?????????? /* 10AAAAAA ,(opcode:10, address:AAAAAA) */
??? temp = 0x80;
??? for(i=0; i<8; i++) {
??????? if(Addr & temp)
??????????? DI = 1;
??????? else
??????????? DI = 0;
??????? Pulse();
??????? temp >>= 1;
??? }

??? rx_data = 0x0000;??????????????????? /* DDDDDDDDDDDDDDDD(16bits data)*/
??? for(i=0; i<16; i++) {
??????? Pulse();
??????? if(DO)
??????????? rx_data |= 0x0001;
??????? if(i < 15)
??????????? rx_data <<= 1;
??? }
??? CS = 0;

??? return(rx_data);
}

void InitPIC(void)
{
??? OPTION = (GPWU | GPPU | PS2 | PS1 | PS0);
??? TRIS = 0x10;???
??? CS = 0;
??? CLK = 0;
??? DI = 0;???
}

/* Main routine */
void main(void)
{
?unsigned char addr;
?unsigned int rx_buf;
?
?InitPIC();
?/* Read a word then +1 and write back to 93LC46 */
?for (addr = 0; addr < 10; addr++)
?{
? rx_buf = Read93LC46(addr);
? rx_buf = rx_buf+1;
? Write93LC46(addr, rx_buf);
?}