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I have a disappointing problem with a keypad module that when pressing on any of its keys, it normally shows up the key pressed on an LCD module. The problem is whenever I press the key, the rows stop being scanned and I have no ability to press any other key to be shown on my LCD if my application, for instance, a system to be recieving a password and shown on the LCD. Another problem facing me right now if I want to show a list on the LCD and I want to turn another page on the screen to resume showing my list. How can I manage to implement this ?!
I'm attaching a screenshot for my schematic plus I'm providing the code for both the keypad and LCD to be checked. And thank you anyway for helping me.
[![enter image description here][1]][1]

[1]: https://i.sstatic.net/E1E9f.jpg

My application code:

#define F_CPU 8000000UL
    #include <util/delay.h>
    #include <avr/io.h>
    #include "LCD.h"
    #include "Keypad.h"

int main(void)
    {
        /* Replace with your application code */
	    uint8_t keypadPress = 0;
	    Keypad_vInit();
	    LCD_vInit();
	
	    while( !Keypad_u8Scan() )
	    {
		    keypadPress = Keypad_u8Scan();
		    if( keypadPress == '8' )
		    {
			    LCD_vPrintChar( '8' );
			    while( keypadPress == '8' );
		    }
	    }
    }

My LCD library:

#if defined MODE_4

static void sendFallingEdge( void ); /* This prototype is declared static       to avoid modifying it. */

static void sendFallingEdge( void )
    {
	    /* Initializing the EN pin of the LCD when detecting a falling edge. */
	    /* The following code is the representation of falling edge using the   system clock. */
	    PORTB |= ( 1 << EN );
	    _delay_ms( 1 );
	    PORTB &= ( ~ ( 1 << EN ) );
	    _delay_ms( 1 );
    }

void LCD_vSendCmd( char cmd )
    {
	    /* Transferring the first nibble. */
	    PORTA &= 0x0F;
	    PORTA |= ( cmd & 0xF0 );
	    CLR_BIT( PORTB, RS ); /* Transferring instructions data. */
	    sendFallingEdge( );
	
	    /* Transferring the second nibble. */
	    PORTA &= 0x0F;
	    PORTA |= ( cmd << 4 );
	    CLR_BIT( PORTB, RS ); /* Transferring instructions data. */
	    sendFallingEdge( );
    }

void LCD_vInit( void )
    {
	    DDRA |= 0xF0; /* DDRA |= 0b11110000; */
	    DDRB |= 0x0E; /* DDRB |= 0b00001110; */ /* Those three HIGH bits are the RS, RW and EN respectively. */
	    CLR_BIT( PORTB, RW ); /* Write mode enabled according to the LCD's datasheet. */
	
	    LCD_vSendCmd( 0x33 );
	    _delay_ms( 1 );
	
	    LCD_vSendCmd( 0x32 );
        _delay_ms( 1 );
	
	    LCD_vSendCmd( 0x28 );
	    _delay_ms( 1 );
	
	    LCD_vSendCmd( 0x01 );
	    _delay_ms( 1 );
	
	    LCD_vSendCmd( 0x0F );
	    _delay_ms( 1 );
    }

void LCD_vPrintChar( char data )
    {
	    PORTA &= 0x0F;
	    PORTA |= ( data & 0xF0 );
	    SET_BIT( PORTB, RS ); /* Transferring display data. */
	    sendFallingEdge( );
	
	    PORTA &= 0x0F;
	    PORTA |= ( data << 4 ); 
	    SET_BIT( PORTB, RS ); /* Transferring display data. */
	    sendFallingEdge( );
    }

void LCD_vPrintString( char * str )
    {
	    uint8_t counter;
	    for( counter = 0; str[ counter ] != '\0'; counter ++ )
	    {
		    LCD_vPrintChar( str[ counter ] );
	    }
    }

void LCD_vPrintNumbers( uint8_t str[ ], uint8_t size )
    {
	    uint8_t counter;
	    for( counter = 0; str[ counter ] < size; counter ++ )
	    {
		    LCD_vPrintChar( str[ counter ] );
	    }
    }

void LCD_vClrScreen( void )
    {
	    LCD_vSendCmd( CLR_SCRN );
    }

void LCD_vMoveCursor( char row, char column )
    {
	    char cmd;
	    if( row == 1 )
	    {
		    cmd = STARTROW0 + column - 1;
		    LCD_vSendCmd( cmd );
	    }
	    else if( row == 2 )
	    {
		    cmd = STARTROW1 + column - 1;
		    LCD_vSendCmd( cmd );
	    }
    }

#endif

My Keypad library:

#include <avr/io.h>
    #include "std_macros.h"

void Keypad_vInit( void )
    {
	    DDRC = 0x0F; 
	    CLR_BIT( SFIOR, PUD ); 
	    PORTC = 0xFF;          
    }
    unsigned char Keypad_u8Scan( void )
    {
	    unsigned char row, column, scan, buttonPressed = 0;
	    unsigned char KP[ 4 ][ 4 ] = { { '7', '8', '9', '/' },
		                               { '4', '5', '6', '*' },
							           { '1', '2', '3', '-' },
								       { ' ', '0', '=', '+' }	  	  	
	                                 };
	    for( row = 0; row < 4; row ++ )
	    {
		    PORTC |= 0x0F;
		    CLR_BIT( PORTC, row );
		    for( column = 4; column < 8; column ++ )
		    {
			    scan = READ_BIT( PINC, column );
			    if( scan == 0 )
			    {
				    buttonPressed = KP[ row ][ column - 4 ];
			    }
		    }
	    }
	    return buttonPressed;
    }

And at last my standard macros:

#define SET_BIT( REGISTER, BIT_NUM ) ( REGISTER = REGISTER | ( 1 << BIT_NUM ) )
    #define CLR_BIT( REGISTER, BIT_NUM ) ( REGISTER = REGISTER & ( ~( 1 << BIT_NUM ) ) )

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