24LCxx系列的讀寫EEPROM的例C語言源程序實例

//************************************************
//* Function: isr_high(void) *
//* High priority interrupt for Timer2 *
//************************************************
#pragma interrupt isr_high

void isr_high(void)
{
PIR1bits.TMR2IF=0; // Clear Timer2 interrupt Flag

if (Debounce==0)
{
if (!SW2)
{ P_SW2=1; Debounce =Bounce_Time; }
if (!SW6)
{ P_SW6=1; Debounce =Bounce_Time; }
}
else if (SW2 SW6)Debounce--;
else Debounce =Bounce_Time;
}
#pragma code

//***********************************************
//* Write a Byte to EEPROM
//* - ctrl : Control Byte of EEPROM
//* - addr : Location of EEPROM
//* - data : Data Byte of EEPROM
//***********************************************

void Initialize_Timer2(void)
{

RCONbits.IPEN=1; // Enable Interrupt Priority bit
IPR1bits.TMR2IP=1; // Set Timer2 for High Priority
INTCONbits.GIEH=1; // Enable High Priority Interrupt

OpenTimer2 (TIMER_INT_ON // Turn On the Timer2 with Interrupt
T2_PS_1_4 // (4Mhz/4) [4*10*(99+1)] = 4mS */
T2_POST_1_10);

PR2 = 99;
}

//***********************************************
//* Write a Byte to EEPROM *
//* - ctrl : Control Byte of EEPROM *
//* - addr : Location of EEPROM *
//* - data : Data Byte of EEPROM *
//***********************************************
void EEPROM_Write(unsigned char ctrl,unsigned char addr,unsigned char data)
{
IdleI2C(); // ensure module is idle
StartI2C(); // Start condition
I2C_Done(); // Wait Start condition completed and clear SSPIF flag

WriteI2C(ctrl); // Write Control+Write to EEPROM Check BF flag
while(SSPCON2bits.ACKSTAT); // wait until received the Acknowledge from EEPROM
I2C_Done(); // Clear SSPIF flag

WriteI2C(addr); // Write Address to EEPROM
while(SSPCON2bits.ACKSTAT); // wait until received the Acknowledge from EEPROM
I2C_Done();

WriteI2C(data); // Write Data to EEPROM
while(SSPCON2bits.ACKSTAT); // wait until received the Acknowledge from EEPROM
I2C_Done();

StopI2C(); // Stop condition
I2C_Done(); // Wait the Stop condition completed
}

//***********************************************
//* Pae Write to EEPROM
//*
//* - ctrl : Control Byte of EEPROM
//* - addr : Location of EEPROM
//* - length : Write counter
//* - *dptr : RAM point --> EEPROM
//*
//***********************************************
void EE_Page_Write(unsigned char ctrl,unsigned char addr,unsigned char length,unsigned char *dptr)
{
IdleI2C(); // ensure module is idle
StartI2C(); // Start condition
I2C_Done(); // Wait Start condition completed

WriteI2C(ctrl); // Write Control+Write to EEPROM Check BF flag
while(SSPCON2bits.ACKSTAT); // wait until received the Acknowledge from EEPROM
I2C_Done(); // Clear SSPIF flag

WriteI2C(addr); // Write Address to EEPROM
while(SSPCON2bits.ACKSTAT); // wait until received the Acknowledge from EEPROM
I2C_Done();

while (length!=0) // Check write completed ?
{
WriteI2C(*dptr); // Write data to EEPROM
while(SSPCON2bits.ACKSTAT); // wait until received the Acknowledge from EEPROM
I2C_Done();
dptr++; // Point to next byte
length--;
}

StopI2C(); // Stop condition
I2C_Done(); // Wait the Stop condition completed
}

//***********************************************
//* EEPROM Acknowledge Polling *
//* -- The routine will polling the ACK *
//* response from EEPROM *
//* -- ACK=0 return *
//* -- ACK=1 send Restart loop check *
//***********************************************
void EEPROM_ACK(unsigned char ctrl)
{
unsigned char i;

IdleI2C(); // ensure module is idle
StartI2C(); // Start condition
I2C_Done(); // Wait Start condition completed

WriteI2C(ctrl); // Write Control to EEPROM (WRITE)
I2C_Done(); // Clear SSPIF flag

while (SSPCON2bits.ACKSTAT) // test for Acknowledge from EEPROM
{
for (i=0;i100;i++); // Delay for next Repet-Start

RestartI2C(); // initiate Repet-Start condition
I2C_Done(); // Wait Repet-Start condition completed

WriteI2C(ctrl); // Write Control to EEPROM (WRITE)
I2C_Done(); // Clear SSPIF flag
}
StopI2C(); // send STOP condition
I2C_Done(); // wait until stop condition is over
}

//***********************************************
//* Random Read a Byte from EEPROM *
//* - ctrl : Control Byte of EEPROM (Write) *
//* (Ctrl +1 ) : Read Command *
//* - addr : Address Byte of EEPROM *
//* - Return : Read Data from EEPROM *
//***********************************************
unsigned char EEPROM_Read(unsigned char ctrl,unsigned char addr)
{
unsigned char f;

IdleI2C(); // ensure module is idle
StartI2C(); // Start condition
I2C_Done(); // Wait Start condition completed

WriteI2C(ctrl); // Write Control to EEPROM
while(SSPCON2bits.ACKSTAT); // test for ACK condition, if received
I2C_Done(); // Clear SSPIF flag

WriteI2C(addr); // Write Address to EEPROM
while(SSPCON2bits.ACKSTAT); // test for ACK condition, if received
I2C_Done(); // Clear SSPIF flag

RestartI2C(); // initiate Restart condition
I2C_Done();

WriteI2C(ctrl+1); // Write Control to EEPROM
while(SSPCON2bits.ACKSTAT); // test for ACK condition, if received
I2C_Done(); // Clear SSPIF flag

f=ReadI2C(); // Enable I2C Receiver wait BF=1 until received data
I2C_Done(); // Clear SSPIF flag

NotAckI2C(); // Genarate Non_Acknowledge to EEPROM
I2C_Done();

StopI2C(); // send STOP condition
I2C_Done(); // wait until stop condition is over

return(f); // Return Data from EEPROM
}

//***********************************************
//* Sequential Read from EEPROM
//*
//* - ctrl : Control Byte of EEPROM
//* - addr : Location of EEPROM
//* - length : Read counter
//* - *dptr : Store EEPROM data to RAM