[PIC] EEprom is reading alternate characters

[MachaniGoutham]

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Code C - [expand]
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#include <proc/p32mx450f128h.h>
#include "uart_fun.h"
// PIC32MX450F128H Configuration Bit Settings
// Configuration Bit settings
// SYSCLK = 48 MHz (8MHz Crystal / FPLLIDIV * FPLLMUL / FPLLODIV)
// PBCLK = 48 MHz (SYSCLK / FPBDIV)
// Primary Osc w/PLL (XT+,HS+,EC+PLL)
// WDT OFF
// Other options are don't care
#pragma config FPLLMUL = MUL_16, FPLLIDIV = DIV_2, FPLLODIV = DIV_4, FWDTEN = OFF
#pragma config POSCMOD = HS, FNOSC = PRIPLL, FPBDIV = DIV_1, JTAGEN = OFF, FSOSCEN = OFF
#pragma config ICESEL = ICS_PGx1
#define SYS_FREQ (16000000L)
#define EEPROM_ID 0xA0
#define BRG_VAL           0x04E
#define ON                1
#define OFF               0
#define STARTI2C1         I2C1CONbits.SEN
#define STOPI2C1          I2C1CONbits.PEN
#define RESTARTI2C1       I2C1CONbits.RSEN
#define ACKI2C1           I2C1CONbits.ACKEN
#define TRANSMITSTATUS_BF I2C1STATbits.TBF
#define RECIEVESTATUS_BF  I2C1STATbits.RBF
#define R_WSTATUS         I2C1STATbits.R_W
#define I2CIDLEBUS        STARTI2C1|STOPI2C1|ACKI2C1|TRANSMITSTATUS_BF|RECIEVESTATUS_BF
 
//function initiates I2C1 module to baud rate BRG
void I2C1_Init()
{
 
   // I2CBRG = 78 for 8Mhz OSCI with PPL with 100kHz I2C clock
   I2C1BRG = BRG_VAL;
   I2C1CONbits.I2CEN = OFF; // Disable I2C Mode
   I2C1CONbits.DISSLW = ON; // Disable slew rate control
   IFS1=0x00;                   // Clear Interrupt
   I2C1CONbits.I2CEN=ON;    // Enable I2C Mode
   I2C1CONbits.SIDL=OFF;        // Module Continues in Idle mode
   I2C1CONbits.A10M=OFF;        // 0=I2CxADD is a 7-bit slave address
   I2C1CONbits.ACKDT = ON;        // setting Ack by  Master operationI
   ACKI2C1 = OFF;
   I2C1RCV=0x00;            // read buffer to clear buffer full
 
    Uart1SendString("I2C Initalized");Uart1Send(0x0D); Uart1Send(0x0A);
}
 
//function iniates a start condition on bus
void I2C1_Start(void)
{
   STARTI2C1= ON;           //Initiate Start condition
   while(STARTI2C1);         //wait for automatic clear before proceding
   Uart1SendString("I2C Started");Uart1Send(0x0D); Uart1Send(0x0A);
}
 
//stop the I2C bus to Idle
void I2C1_Stop(void)
{
    //initiate stop bit
    STOPI2C1= ON;
   //wait for hardware clear of stop bit
   while (STOPI2C1);
   Uart1SendString("I2C Stoped");Uart1Send(0x0D); Uart1Send(0x0A);
}
 
//restart i2c bus
void I2C1_Restart(void)
{
 
    RESTARTI2C1=ON; //Initiate restart condition
 
   //the hardware will automatically clear restart bit
   //wait for automatic clear before proceding
   while (RESTARTI2C1);
 
Uart1SendString("I2C Restarted");Uart1Send(0x0D); Uart1Send(0x0A);
}
 
//I2C Idle state
void IdleI2C()
{
    if(I2CIDLEBUS);
    Uart1SendString("I2C @ IDLE STATE");Uart1Send(0x0D); Uart1Send(0x0A);
}
 
// write I2C
void WriteI2C1(unsigned char data)
{
    unsigned char x;
    IdleI2C();
 
    I2C1TRN = data; // load the outgoing data byte
    x=I2C1TRN;
    while (I2C1STATbits.TRSTAT);   // wait untill TBF-1 transmit is in progress...0-transmit Completed
Uart1SendString("I2C Write completed");Uart1Send(x);
 
Uart1Send(0x0D); Uart1Send(0x0A);
}
 
 //function reads data I2C,
unsigned char ReadI2C1(void)    //does not reset bus!!!
{
  unsigned char data;
 
   I2C1CONbits.RCEN = 1;      //set I2C module to receive
 
   while(I2C1CONbits.RCEN){};
   I2C1STATbits.I2COV=0;    // update to I2CRCV register clearing manually
 
   while(I2C1STATbits.RBF){ // wait to clear recive buffer
      data = I2C1RCV;          //get data from I2CRCV register
   }
 
Uart1SendString("Read Completed");
Uart1Send(0x0D); Uart1Send(0x0A);
 return data;               //return data
 
}
 
// ACK I2C1
void Ackl2C (void)
{
 I2C1CONbits.ACKDT = OFF;        // setting Ack by  Master operationI
 ACKI2C1 = ON;                 //Ack enabled
 while(ACKI2C1);              // wait Nack cleared
}
 
// NACK I2C1
void Nackl2C (void)
{
 I2C1CONbits.ACKDT = ON;        // setting Ack by  Master operationI
 ACKI2C1 = ON;                 //Ack enabled
 
}
 
unsigned char EEByteWrite(unsigned char c, unsigned char address,  unsigned char data)
{
 
    IdleI2C();           // ensure I2C bus is idle
    I2C1_Start( );      // initiate START condition
 
        if (I2C1STATbits.BCL)  // test for bus collision
            return (-1);  // return with Bus Collision error
 
    WriteI2C1(c);  // write byte - R/W bit should be 0
    IdleI2C();   // ensure module is idle
 
        if (I2C1STATbits.ACKSTAT)  // test for NACK condition received
        return (-2);
 
    WriteI2C1(address);  // write word address for EEPROM
    IdleI2C();  // ensure module is idle
 
        if (I2C1STATbits.ACKSTAT)  // test for NACK condition received
        return (-2);
 
    WriteI2C1(data);  // data byte for EEPROM
    IdleI2C();  // ensure module is idle
 
    I2C1_Stop();  // send STOP condition
        if (I2C1STATbits.BCL)  // test for bus collision
        return (-1);  // return with Bus Collision error
 Uart1SendString("EEprom write Sucess");
return (0);  // return with no error
}
 
 
unsigned char EERandomRead( unsigned char c, unsigned char address)
{
   unsigned char edata;
 
   IdleI2C();      // make sure I2C module is idle
   I2C1_Start();   // assert a START condition
 
   WriteI2C1(c);  // write byte - R/W bit should be 0
   IdleI2C();   // ensure module is idle
 
        if (I2C1STATbits.ACKSTAT)  // test for NACK condition received
        return (-2);
 
   WriteI2C1(address);  // write word address for EEPROM
   IdleI2C();  // ensure module is idle
 
        if (I2C1STATbits.ACKSTAT)  // test for NACK condition received
        return (-2);
 
   I2C1_Restart();  // assert I2C bus restart condition
         if (I2C1STATbits.BCL)  // test for bus collision
            return (-1);  // return with Bus  Collision error
 
   WriteI2C1(0xA1);  // write 1 byte - R/W bit should be 1
   IdleI2C();  // ensure module is idle
 
        if (I2C1STATbits.ACKSTAT)  // test for NACK condition received
        return (-2);
 
   edata=ReadI2C1();
 
   Nackl2C ();
 
   while(ACKI2C1);
 
   I2C1_Stop();  // send STOP condition
 
      if (I2C1STATbits.BCL)  // test for bus collision
         return (-1);  // return with Bus Collision error
 
 Uart1SendString("EEprom read Sucess");
 Uart1Send(0x0D); Uart1Send(0x0A);
 
return edata;  // return with data
}
 
void DelayuSec(unsigned int n)     //loop nops for delay
{
   unsigned int j;
   while(n>0)
   {
      for(j=0;j < 10; j++);
         n--;
   }
}
 
 
 
void main()
{
    unsigned char Eodata[14],i,address;
    UART1PPSInit();
    UART1Initialise();
    Uart1SendString("uartworking");Uart1Send(0x0D); Uart1Send(0x0A);
 
    I2C1_Init();
 
     EEByteWrite(0xA0,0x00,'G');
    EEByteWrite(0xA0,0x01,'o');
   EEByteWrite(0xA0,0x02,'u');
   EEByteWrite(0xA0,0x03,'t');
    EEByteWrite(0xA0,0x04,'h');
    EEByteWrite(0xA0,0x05,'a');
    EEByteWrite(0xA0,0x06,'m');
    EEByteWrite(0xA0,0x07,'R');
     EEByteWrite(0xA0,0x08,'o');
EEByteWrite(0xA0,0x09,'c');
    EEByteWrite(0xA0,0x0A,'k');
    EEByteWrite(0xA0,0x0B,'z');
     EEByteWrite(0xA0,0x0C,'O');
     EEByteWrite(0xA0,0x0D,'n');
        Eodata[0]=EERandomRead(0xA0,address); Uart1Send(Eodata[0]);
    address=0x00;
    for(i=0;i<14;i++){
    Eodata[i]=EERandomRead(0xA0,address);
   address++;
    }
//     Uart1Send(0x0D); Uart1Send(0x0A);
//     for(i=0;i<14;i++){
//         Uart1Send(Eodata[i]);
//     }
//     Uart1Send(x);
      Uart1SendString(Eodata);
 
}

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[FvM]

And the question is?

 

[horace1]

cannot see any obvious error

have you had a look at the microchip example PIC32 MEB - EEPROM Demo using I2C

https://ww1.microchip.com/downloads/en/DeviceDoc/PIC32_MEB_EEPROM_Demo_042611.zip

 

[MachaniGoutham]

Thanks for answering there is no error on code
but it executes alternate characters from eeprom

 

[horace1]

I was not thinking of syntax errors which the compiler finds but errors in the logic of the code where it may not be reading/writing the EEPROM correctly

I note you have UART output in WriteI2C1, I2C1_Stop, I2C1_Rstart, etc
outputing to a UART can slow things significantly (unless you are using UART transmit interrupts) - could these outputs be throwing the I2C timing out? try commenting them out?

 

[milan.rajik]

What do you mean by alternate characters. Give example. You mean 'G', 'u' , 'h'... like that ?

 

[MachaniGoutham]

What do you mean by alternate characters. Give example. You mean 'G', 'u' , 'h'... like that ?

yes,sir what you guess is right

 

[milan.rajik]

Each memory location is byte size or word size in your MCU's EEPROM ?