[PIC] Pic16lf1823_nxp Write Program

Code C - [expand]
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#include <stdio.h>
#include <stdlib.h>
 
#include <xc.h> // include standard header file
 
 
// Set Config bits - we are using internal oscillator without the PLL
#pragma config FOSC=INTOSC, PLLEN=OFF, MCLRE=ON, WDTE=OFF
#pragma config LVP=OFF, CLKOUTEN=OFF,
 
 
// Definitions
#define _XTAL_FREQ  16000000        // this is used by the __delay_ms(xx) and __delay_us(xx) functions
#define device_control_code_NXP  0b1010 // All I2C devices have a control code assigned to them.
                                    // and the control code for a serial eeprom is b'1010'
 
 
//**************************************************************************************
// Send one byte to SEE
//**************************************************************************************
void Send_I2C_Data(unsigned int databyte)
{
    PIR1bits.SSP1IF=0;          // clear SSP interrupt bit
    SSPBUF = databyte;              // send databyte
    while(!PIR1bits.SSP1IF);    // Wait for interrupt flag to go high indicating transmission is complete
}
 
//**************************************************************************************
// Read one byte from SEE
//**************************************************************************************
unsigned int Read_I2C_Data(void)
{
    PIR1bits.SSP1IF=0;          // clear SSP interrupt bit
    SSPCON2bits.RCEN=1;         // set the receive enable bit to initiate a read of 8 bits from the serial eeprom
    while(!PIR1bits.SSP1IF);    // Wait for interrupt flag to go high indicating transmission is complete
    return (SSPBUF);            // Data from eeprom is now in the SSPBUF so return that value
}
 
void Send_I2C_ControlByte_NXP(unsigned int BlockAddress,unsigned int RW_bit)
{
    PIR1bits.SSP1IF=0;          // clear SSP interrupt bit
SSPBUF = ((device_control_code_NXP << 4) | (BlockAddress <<1)) + RW_bit;  // send the control byte
    while(!PIR1bits.SSP1IF);    // Wait for interrupt flag to go high indicating transmission is complete
}
 
//**************************************************************************************
// Send start bit to SEE
//**************************************************************************************
void Send_I2C_StartBit(void)
{
    PIR1bits.SSP1IF=0;          // clear SSP interrupt bit
    SSPCON2bits.SEN=1;          // send start bit
    while(!PIR1bits.SSP1IF);    // Wait for the SSPIF bit to go back high before we load the data buffer
}
 
//**************************************************************************************
// Send stop bit to SEE
//**************************************************************************************
void Send_I2C_StopBit(void)
{
    PIR1bits.SSP1IF=0;          // clear SSP interrupt bit
    SSPCON2bits.PEN=1;          // send stop bit
    while(!PIR1bits.SSP1IF);    // Wait for interrupt flag to go high indicating transmission is complete
}
 
 
//**************************************************************************************
// Send ACK bit to SEE
//**************************************************************************************
void Send_I2C_ACK(void)
{
   PIR1bits.SSP1IF=0;          // clear SSP interrupt bit
   SSPCON2bits.ACKDT=0;        // clear the Acknowledge Data Bit - this means we are sending an Acknowledge or 'ACK'
   SSPCON2bits.ACKEN=1;        // set the ACK enable bit to initiate transmission of the ACK bit to the serial eeprom
   while(!PIR1bits.SSP1IF);    // Wait for interrupt flag to go high indicating transmission is complete
}
 
//**************************************************************************************
// Send NAK bit to SEE
//**************************************************************************************
void Send_I2C_NAK(void)
{
    PIR1bits.SSP1IF=0;           // clear SSP interrupt bit
    SSPCON2bits.ACKDT=1;        // set the Acknowledge Data Bit- this means we are sending a No-Ack or 'NAK'
    SSPCON2bits.ACKEN=1;        // set the ACK enable bit to initiate transmission of the ACK bit to the serial eeprom
    while(!PIR1bits.SSP1IF);    // Wait for interrupt flag to go high indicating transmission is complete
}
 
void main() {
 
    unsigned int ACK_bit;
    volatile unsigned int eeprom_data;//,incoming_data;
    volatile unsigned int block_address, word_address1, word_address2;
 
 
    word_address1 = 0x20;    // Set the eeprom word address that we will write the data to
    word_address2 = 0x04;    // Set the eeprom word address that we will write the data to
    eeprom_data = 0x11;     // This is the data  we are going to write
 
 
// set up oscillator control register
    OSCCONbits.IRCF = 0x0F; //set OSCCON IRCF bits to select OSC frequency=16Mhz
    OSCCONbits.SCS = 0x02; //set the SCS bits to select internal oscillator block
 
    //  PORT C Assignments
    TRISCbits.TRISC0 = 1; // RC0 = SCL signal to SEE (must be set as input)
    TRISCbits.TRISC1 = 1; // RC1 = SDA signal to SEE (must be set as input)
    TRISCbits.TRISC2 = 0; // RC2 = nc
    TRISCbits.TRISC3 = 0; // RC3 = nc
    TRISCbits.TRISC4 = 0; // RC4 = nc
    TRISCbits.TRISC5 = 0; // RC5 = nc
 
 
//**********************************************************************************
 
    SSPCONbits.SSPM=0x08;       // I2C Master mode, clock = Fosc/(4 * (SSPADD+1))
    SSPCONbits.SSPEN=1;         // enable MSSP port
 
    // **************************************************************************************
 
    SSPADD = 39;                // set Baud rate clock divider
    // **************************************************************************************
 
    __delay_ms(10); // let everything settle.
 
 
        // ******************************************************************************
        // ***********  write a single byte of data to address of 5NXP)  **************
        // *******************************************************************************
        Send_I2C_StartBit();                    // send start bit
        Send_I2C_ControlByte_NXP(block_address,0);  // send control byte with R/W bit set low
 
        // The Most significant byte is sent first, followed by the least significant byte
        Send_I2C_Data(word_address1);            // send word address
        Send_I2C_ACK();
        Send_I2C_Data(word_address2);            // send word address
        ACK_bit = 1;            // init the Ack bit high
       
                Send_I2C_StartBit();
                Send_I2C_ControlByte_NXP(block_address,0);
                ACK_bit = SSPCON2bits.ACKSTAT;  // Ack bit will come back low when the write is complete
            
        Send_I2C_Data(eeprom_data);             // send data byte
        Send_I2C_StopBit();                     // send stop bit
 
 
}