/*-------------------------------------------------------------------
**
**  Soluciones del examen de Programación de Sistemas y Dispositivos
**  Curso 2017-18, Segunda Convocatoria, 6 de julio de 2018
**
**-----------------------------------------------------------------*/

/*-------------------------------------------------------------------
**    Ejercicio 1
**-----------------------------------------------------------------*/

#include <s3c44b0x.h>
#include <common_types.h>
#include <system.h>
#include <uart.h>
#include <timers.h>
#include <keypad.h>

void timer0_isr( void ) __attribute__ ((interrupt ("IRQ")));

volatile boolean flag;
volatile char ch;

void main( void )
{
    sys_init();
    uart0_init();
    timers_init();
    keypad_init();

    flag = FALSE;
    timer0_open_ms( timer0_isr, 20, TIMER_INTERVAL );
    while( 1 )
    {
        ch = keypad_getchar();
        ch += ( ch < 10 ? '0' : 'a'-10 );
        flag = TRUE;
    }
}

void timer0_isr( void )
{
    if( flag && !(UFSTAT0 & (1 << 9)) )
    {
        UTXH0 = ch;    
        flag = FALSE;
    }

    I_ISPC = BIT_TIMER0;
}

/*-------------------------------------------------------------------
**    Ejercicio 2
**-----------------------------------------------------------------*/

#include <common_types.h>
#include <fix_types.h>

fix16 fix_add( fix16 a, uint8 an, fix16 b, uint8 bn )
{
    uint8 rm;
    fix32 a32, b32, r32;

    if( an >= bn ) {
        rm = an;
        a32 = a;
        b32 = b << (an-bn);
    }
    else {
        rm = bn;
        a32 = a << (bn-an);
        b32 = b;
    }

    r32 = a32 + b32;

    if( r32 > MAX_INT16 )
        return MAX_INT16;
    else if ( r32 < MIN_INT16 )
        return MIN_INT16;
    else
        return r32;

}

/*-------------------------------------------------------------------
**    Ejercicio 3
**-----------------------------------------------------------------*/

#include <s3c44b0x.h>
#include <common_types.h>
#include <iis.h>

inline void iis_putSampleMono( int16 sample )
{
    while( ((IISFCON & 0xF0) >> 4) > 6 );
    IISFIF = sample;
    IISFIF = sample;
}


inline int16 iis_getSampleMono( void )
{
    int16 trash;
    
    while( (IISFCON & 0x0F) < 2 );
    trash = IISFIF;
    return IISFIF;
}

/*

inline void iis_putSampleMono( int16 sample )
{
    iis_putSample( sample, sample );
}

inline int16 iis_getSampleMono( void )
{
    int16 trash, sample;

    iis_getSample( &trash, &sample );
    return sample;
}

*/

/*-------------------------------------------------------------------
**    Ejercicio 4
**-----------------------------------------------------------------*/


#include <common_types.h>
#include <lcd.h>

extern uint8 font[];

void lcd_putchar_transparent( uint16 x, uint16 y, uint8 color, char ch )
{
    uint8 row, col;
    uint8 *bitmap;

    bitmap = font + ch*16;
    for( row=0; row<16; row++ )
        for( col=0; col<8; col++ )                    
            if( bitmap[row] & (0x80 >> col) )
                lcd_putpixel( x+col, y+row, color );
}