storing characters in EEPROM & echoing back

Am trying to write a program for AVR STK600 board in which am cycling through LEDs. When a switch is pressed, appropriate LEDs turns on (upto this point, everything goes well). Now am adding another functionality to the board, trying to use USART (RS232 serial communication).

-When a user presses a key, it should be echoed (on hyperterminal). -When crtl-Z is hit, the data should be recorded in EEPROM (again hitting crtl-z should stop recording). -When crtl-y is pressed, the recorded data should be played back.

The problem here am getting is with USART (I did check all my hardware settings, did loopback test...everything is working well) so there should be some problem with the code. Upto toggling the LEDs everything goes well after that EEPROM, USART is not going well.

Here is my code, am using AVR-GCC. Also am not using "avrlib" because the course am taking doesn't allow us to do so:

#include "header.h"

#define BASE_ADDR   0x20

#define READ_ATMEGA(ADDR)   *((P_CHAR)(BASE_ADDR + ((ADDR) * ADDR_MULTIPLIER)))

#define WRITE_ATMEGA(ADDR, DATA)    *((P_CHAR)(BASE_ADDR + ((ADDR) * ADDR_MULTIPLIER))) = DATA

#define LED_DELAY 10

#define F_CPU 8000000

#define BAUDRATE 9600

#define BAUD_PRESCALER (((F_CPU/(BAUDRATE * 16UL)))-1)

volatile UINT intrs, i = 1, count, switch_pressed = 0, uiAdd, uiAddEnd, flag_led_intr;
volatile UINT record, play_recorded_keys, RX, flag_serial_receiver, TX_complete; 

volatile unsigned char get_switch=0, data;

extern void __vector_23 (void) __attribute__ ((interrupt)); 
extern void __vector_25 (void) __attribute__ ((signal)); 
extern void __vector_27 (void) __attribute__ ((interrupt)); 

void enable_ports(void); 
int get_switchpressed(void);
void call_interruptHandler(void);
void usart_init(void); 
//void usart_bounce();
void initialize(void);
void ReadWriteSerialPort(void);
void EEPROM_write(unsigned int uiAddress, unsigned char ucData);
unsigned char EEPROM_read(unsigned int uiAddress);


void initialize(void)
{
    cli();      //stop all interrupts

    flag_led_intr = 0;
    record = 0;
    play_recorded_keys = 0;
    RX = 0;
    flag_serial_receiver = 0;

    uiAdd = 0;
    uiAddEnd = 0;
    TX_complete = 0;

    enable_ports();
    usart_init();

    sei();
}

void enable_ports() //Enables PORTB, PORTD & TIMER
{ 

    WRITE_ATMEGA(DDRB,0xff);    //PORTB as output for leds 

    WRITE_ATMEGA(PORTB,0xff);   //Initialize PORTB

    WRITE_ATMEGA(DDRD, 0x00);    //PORTD as input for switches

    WRITE_ATMEGA(TCCR0B, 0x05);     //Setting TIMER to 1024 prescaler

    WRITE_ATMEGA(TIMSK0, 0x01); 

    WRITE_ATMEGA(TCNT0, 256-LED_DELAY);

    intrs = 0; 
} 

void usart_init(void) //Enables USART
{ 
   /* Set baud rate */ 

   WRITE_ATMEGA(UBRR0L, BAUD_PRESCALER); 
   WRITE_ATMEGA(UBRR0H,(BAUD_PRESCALER>>8)); 

   /* Set frame format: 8 bit data + start bit + stop bit */ 

   WRITE_ATMEGA(UCSR0C, 0x06);

   /* Enable reciever and transmitter */ 

   WRITE_ATMEGA(UCSR0B, 0xD8); 
} 


void __vector_23 (void)
{ 
   call_interruptHandler();
}

void __vector_25 (void)
{ 
    RX = UDR0;
    flag_serial_receiver = 1;
    sei();
}

void __vector_27 (void)
{
    TX_complete = 1;
}
void call_interruptHandler()
{
    intrs++;
    if(intrs > LED_DELAY)
    {
        WRITE_ATMEGA(PORTB, 0xff<<i);
        i++;

        if(i==10)
        {
            WRITE_ATMEGA(PORTB, 0xff);
            i = 1;
        }
    }

    count = get_switchpressed();

    if(count != 0) 
    {
        WRITE_ATMEGA(PORTB, 0xff<<count); 
        intrs = 0;

    }

   //sei(); 
} 

int get_switchpressed()
{ 

    get_switch = READ_ATMEGA(PIND);

    switch(get_switch) {

        case 0xFE:  
                switch_pressed = 1;
                break;

        case 0xFD:  
                switch_pressed = 2;
                break;

        case 0xFB:  
                switch_pressed = 3;
                break;

        case 0xF7:  
                switch_pressed = 4;
                break;

        case 0xEF:
                switch_pressed = 5;
                break;

        case 0xDF:
                switch_pressed = 6;
                break;

        case 0xBF:
                switch_pressed = 7;
                break;

        case 0x7F:
                switch_pressed = 8;
                break;

    };

    return (switch_pressed);
}

void ReadWriteSerialPort(void)
{
    if(RX == 0x1A)
    {
        record = !record;
        play_recorded_keys = 0;
    }

    else if(RX == 0x19)
    {
        record = 0;
        play_recorded_keys = !play_recorded_keys;
    }

    if(record)
    {
        EEPROM_write(uiAdd++, RX);
    }
    if(uiAdd == 4096)
    {
        record = 0;
        uiAddEnd = 4096;
    }
    else
        uiAddEnd = uiAdd;
}   

void EEPROM_write(unsigned int uiAddress, unsigned char ucData)
{
    while(EECR & (1<<EEPE));            /* Wait for completion of previous write */

    WRITE_ATMEGA(EEARH,(uiAddress>>8)); /* Set up address and Data Registers */
    WRITE_ATMEGA(EEARL, uiAddress);

    WRITE_ATMEGA(EEDR, ucData);

    WRITE_ATMEGA(EECR, (EECR |(1<<EEMPE))); /* Write logical one to EEMPE */

    WRITE_ATMEGA(EECR, (EECR |(1<<EERE)));  /* Start eeprom write by setting EEPE */
}

unsigned char EEPROM_read(unsigned int uiAddress)
{
    while(EECR & (1<<EEPE));    /* Wait for completion of previous write */

    WRITE_ATMEGA(EEARH,(uiAddress>>8));     /* Set up address register */
    WRITE_ATMEGA(EEARL,uiAddress);

    WRITE_ATMEGA(EECR, (EECR |(1<<EERE)));      /* Start eeprom read by writing EERE */
    return EEDR;            /* Return data from Data Register */
}

int main(void) 
{ 
   initialize(); 
   while(1) 
   { 
        if(flag_serial_receiver == 1)
        {
            flag_serial_receiver = 0;
            ReadWriteSerialPort();
        }
        if(play_recorded_keys)
        {
            unsigned char TX = EEPROM_read(uiAdd++);

            if(uiAdd == 4096 || uiAdd >= uiAddEnd)
            {
                play_recorded_keys = 0;
                uiAdd = 0;
            }

            while((UCSR0A & (1<<UDRE0)) == 0);
            WRITE_ATMEGA(UDR0,TX);

            while(TX_complete == 0);
                TX_complete;
        }

   } 
return(0);
}

Here is the header.h file

#ifndef HEADER_H

#define HEADER_H

/*******PORTS******************/

#define PINA  0x0
#define DDRA  0x1
#define PORTA 0x2

#define PINB  0x3
#define DDRB  0x4
#define PORTB 0x5

#define PINC  0x6
#define DDRC  0x7
#define PORTC 0x8

#define PIND  0x9
#define DDRD  0xA
#define PORTD 0xB

#define PINE  0xC
#define DDRE  0xD
#define PORTE 0xE

#define PINF  0xF
#define DDRF  0x10
#define PORTF 0x11

#define PING  0x12
#define DDRG  0x13
#define PORTG 0x14

#define PINH  0xE0
#define DDRH  0xE1
#define PORTH 0xE2

#define PINJ  0xE3
#define DDRJ  0xE4
#define PORTJ 0xE5

#define PINK  0xE6
#define DDRK  0xE7
#define PORTK 0xE8

#define PINL  0xE9
#define DDRL  0xEA
#define PORTL 0xEB


/************TIMERS ************/
#define TCCR0A  0x24  
#define TCCR0B  0x25  
#define TCNT0   0x26  
#define OCR0A   0x27  
#define OCR0B   0x28  
#define TIMSK0  0x4E  
#define TIFR0   0x15  
#define COM0A1  0x7   
#define COM0A0  0x6   
#define COM0B1  0x5   
#define COM0B0  0x4   
#define WGM02   0x3   
#define WGM01   0x1   
#define WGM00   0x0   
#define CS02    0x2   
#define CS01    0x1   
#define CS00    0x0   
#define OCIE0B  0x2   
#define OCIE0A  0x1   
#define TOIE0   0x0   


/****** Interrupts *******/
#define EICRA   0x49  
#define EICRB   0x4A  
#define EIMSK   0x1D  

#define PCICR   0x48
#define PCMSK0  0x4B
#define PCMSK1  0x4C
#define PCMSK2  0x4D

/************EEPROM************/

#define EECR    0x1F

#define EEDR    0x20

#define EEARL   0x21

#define EEARH   0x22

#define EEAR0   0
#define EEAR1   1
#define EEAR2   2
#define EEAR3   3
#define EEAR4   4
#define EEAR5   5
#define EEAR6   6
#define EEAR7   7
#define EEAR8   8
#define EEAR9   9
#define EEAR10  10
#define EEAR11  11

#define LSB     0
#define MSB     7

#define EERE    0
#define EEPE    1
#define EEMPE   2
#define EERIE   3
#define EEPM0   4
#define EEPM1   5



/************UART Status Control Registers & Data Registers **************/

/** USART3 **/
#define UCSR3A      0x130 
#define UCSR3B      0x131 
#define UCSR3C      0x132 
#define UBRR3L      0x134 
#define UBRR3H      0x135 
#define UDR3        0x136 
#define UDR3_TXB    UDR3  /* transmit data buffer register */
#define UDR3_RXB    UDR3  /* receive data buffer register  */

/** USART2 **/

#define UDR2        0xD6
#define UBRR2H      0xD5
#define UBRR2L      0xD4
#define UCSR2C      0xD2
#define UCSR2B      0xD1
#define UCSR2A      0xD0
#define UDR2_TXB    UDR2  /* transmit data buffer register */
#define UDR2_RXB    UDR2  /* receive data buffer register  */

/** USART1 **/
#define UDR1        0xCE    
#define UBRR1H      0xCD
#define UBRR1L      0xCC    
#define UCSR1C      0xCA
#define UCSR1B      0xC9
#define UCSR1A      0xC8
#define UDR1开发者_开发百科_TXB    UDR1  /* transmit data buffer register */
#define UDR1_RXB    UDR1  /* receive data buffer register  */

/** USART0 **/
#define UDR0        0xC6    
#define UBRR0H      0xC5
#define UBRR0L      0xC4    
#define UCSR0C      0xC2
#define UCSR0B      0xC1
#define UCSR0A      0xC0
#define UDR0_TXB    UDR0  /* transmit data buffer register */
#define UDR0_RXB    UDR0  /* receive data buffer register  */

#define TXB80       0
#define RXB80       1
#define UCSZ02      2
#define TXEN0       3
#define RXEN0       4
#define UDRIE0      5
#define TXCIE0      6
#define RXCIE0      7

#define MPCM0   0
#define U2X0    1
#define UPE0    2
#define DOR0    3
#define FE0     4
#define UDRE0   5
#define TXC0    6
#define RXC0    7

#define UCPOL0  0
#define UCSZ00  1
#define UCSZ01  2
#define USBS0   3
#define UPM00   4
#define UPM01   5
#define UMSEL00 6
#define UMSEL01 7

/******************************/

# define sei()  __asm__ __volatile__ ("sei" ::)

# define cli()  __asm__ __volatile__ ("cli" ::)


/* vectors in AVR are hard cided to a function by name */
extern void __vector_23 (void) __attribute__ ((interrupt));

/* interrupt is disabled at initilization */
extern void __vector_11 (void) __attribute__ ((interrupt));


/*******ADDR_MULTIPLIER********/

#define ADDR_MULTIPLIER     1


/*******Type Declaration*******/

#define UINT unsigned int
#define P_CHAR volatile unsigned char *



/***LEDs ON-OFF Declaration****/

#define LED_ON      0x00
#define LED_OFF     0xff

#endif

I would highly appreciate if someone could help me solving this puzzle as am badly drowning under it.

Thanks in advance.

Well, it's a bit hard to check the entire code, it's long and of course there could be a lot of bad things setted on the AVR...

I think you should first remove all LED's code and just try that UART recorder alone, until it works.

The only thing I saw was that you do:

unsigned char TX = EEPROM_read(uiAdd++);

but you do not set uiAdd to start from 0...

Anyway, I'm not sure because it's hard to follow the program flow.