Kann keine Daten für 24c256 EEPROM schreiben?

Ich verwende den Pic24fj128ga202-Mikrocontroller und das 24c256-EEPROM und die ISL1208-RTC, die über den I2c-Bus verbunden sind. Das Problem ist, dass ich die Daten in EEPROM und RTC lesen und schreiben kann, aber auf einigen anderen Boards (mit demselben Design) kann ich die Daten nicht über den i2c-Bus lesen oder schreiben. Ich habe meinen Code und meinen Schaltplan gepostet. Bitte spricht mich jemand an, was ist das Problem? Ich habe kein Oszilloskop, um das zu überprüfen.

#include <stdio.h>
#include "C:\Program Files\Microchip\xc16\v1.24\support\PIC24F\h\p24FJ128GA202.h"
#include "uart.h"
// calculate baud rate of I2C
#define Fosc      32000000
#define Fcy       (Fosc/2)
#define Fsck      400000
#define I2C_BRG  ((Fcy/2/Fsck)-1)

int main()
{
    InitProcessor();
    Delayms();
    while(1)
    {
        I2c_Write(0xA0,1,'A');
        Delayms(5000);
        uart1tx(I2C_read(0xA0,1));
    }
}

void InitProcessor(void)
{
    // Oscillator    8mhz no pll
    OSCCON = 0x0011;
    CLKDIV = 0x0000; 

    // Configure Digital pins
    ANSA = 0x0003;
    ANSB = 0x0000;

    //  Assign  IO values for Ports
    PORTA = 0x0000;
    TRISA = 0x001B;
    TRISB = 0x468f;                   // 7 as receive and 8 as transmitter
    //PORTB = 0x0000;


    // Interrupt Bits 
    INTCON1 = 0x0000;                                               // Disable  Interrupts
    INTCON2 = 0x0000;

    // Init I2C
    I2C2CONL = 0x8000;
    I2C2CONH = 0x0000;
    I2C2STAT = 0x0000;
    I2C2BRG = I2C_BRG;
    //I2C2BRG = 79;

    Delayms(1000);
    Init_rtc();
}

void Init_rtc()
{
    I2c_Write(0xde, 0x07, 0x10);
    I2c_Write(0xde, 0x06, 0x00);
    Delayms(20);
}

void I2c_Write(unsigned char DeviceAddress,unsigned int Addr,unsigned char i2c_value)
{
    unsigned char i2c_exit=1,i2c_write=0;
    int I2creg = 0;
    IFS3 &= ~0x0004;
    I2C2CONL |= 0x0001;
    I2cTimer = 0;
    while(i2c_exit)
    {
        if(I2cTimer > 30){                                              // Exit routine
            i2c_exit = 0;
        }
        if(IFS3& 0x0004)
        {
            IFS3 &= ~0x0004;
            I2cTimer = 0;
            if(i2c_write == 0)
            {
                I2C2TRN = (DeviceAddress & 0xfe);
                if(DeviceAddress == 0xde)
                    i2c_write = 1;
            }
            else if(i2c_write == 1)
                I2C2TRN = Addr >> 8;
            else if(i2c_write == 2)
                I2C2TRN = Addr & 0xFF;
            else if(i2c_write == 3)
                I2C2TRN = i2c_value;
            else if(i2c_write == 4)
                I2C2CONL |= 0x04;
            else
            {
                i2c_write = 100;
                i2c_exit = 0;
            }
            i2c_write++;
        }
    }
    Delayms(5);
}

/* Function to Read and return a data through I2C  */
unsigned char I2C_read(unsigned char DeviceAddress,unsigned int Addr)
{   unsigned char db, ReadState=0,I2CFlag;
    ReadState = 0;
    IFS3 &= ~0x0004;                                                        // Master I2C interrupt flag
    I2CFlag = 1;
    I2C2CONL |= 0x0001;         // SEN = 1;
    I2cTimer = 0;
    while(I2CFlag){
        if(I2cTimer > 30){                                              // Exit routine
            I2CFlag = 0;

            //ModemDiagnostics(64,1);
        }
        //uart1tx('r');
        if(IFS3 & 0x0004)
        {       
            I2cTimer = 0;
            IFS3 &= ~0x0004;
            if(ReadState == 0)
            {
                I2C2TRN = (DeviceAddress & 0xfe);
                if(DeviceAddress == 0xde)
                    ReadState = 1;
            }
            else if(ReadState == 1)
                I2C2TRN = Addr >> 8;
            else if(ReadState == 2)
                I2C2TRN = Addr & 0xff;
            else if(ReadState == 3)I2C2CONL |= 0x0002;  
            else if(ReadState == 4)I2C2TRN = (DeviceAddress | 0x01);
            else if(ReadState == 5){
                I2C2CONL |= 0x0008;                             // RCEN = 1, Enable data receive
                db = I2C2RCV;
            }
            else if(ReadState == 6){
                db = I2C2RCV;                                                       // Read Data
                I2C2CONL |= 0x0020;                                                 // ACKDT = 1, Set Acknowledge bit (No Acknowledge)
                Delayms(5);
                I2C2CONL |= 0x0010;                                                 // ACKEN = 1
            }
            else if(ReadState == 7)I2C2CONL |= 0x04;                                // PEN = 1, Stop enable bit forI2C
            else{ReadState = 100; I2CFlag = 0;}                                     
            ReadState++;
        }
    }
    if(db)
        return db;
    else
        return 0;
}