/** 
 * @mainpage Large Display Clock
 *
 * @section overview_sec Overview
 *
 * Large display LED clock.
 *
 * @section history_sec Revision History
 *
 * @subsection v100 V1.00
 * <b>5 Mar 2006</b>, <i>M.Gray</i>, Initial release
 */

// Hardware specific configuration.
#include <18f252.h>

// External crystal oscillator.
#fuses HS

// Disable watch dog timer.
#fuses NOWDT

// Protect the code so it can't be read back.
#fuses NOPROTECT

// Disable the power-up enable timer.
#fuses NOPUT

// Disable the brown out detect.
#fuses NOBROWNOUT

// Disable the low voltage programming mode.
#fuses NOLVP


// We define types that are used for all variables.  These are declared
// because each processor has a different sizes for int and long.
// The PIC compiler defines boolean, int8, int16, and int32.

/// Boolean value { false, true }
typedef boolean bool_t;

/// Signed 8-bit number in the range -128 through 127.
typedef signed int8 int8_t;

/// Unsigned 8-bit number in the range 0 through 255.
typedef unsigned int8 uint8_t;

/// Signed 16-bit number in the range -32768 through 32767.
typedef signed int16 int16_t;

/// Unsigned 16-bit number in the range 0 through 65535.
typedef unsigned int16 uint16_t;

/// Signed 32-bit number in the range -2147483648 through 2147483647.
typedef signed int32 int32_t;

/// Unsigned 32-bit number in the range 0 through 4294967296.
typedef unsigned int32 uint32_t;

/// IEEE 32-bit floating point number.
typedef struct
{
    /// Array that holds 32-bit IEEE floating pointer number.
    unsigned int8 value[4];
} float_t;

/// IEEE 64-bit floating point number.
typedef struct
{
    /// Array that holds 64-bit IEEE floating point number.
    unsigned int8 value[8];
} double_t;

// These compiler directives set the clock, SPI/I2C ports, and I/O configuration.

// Frequency of crystal
#use delay(clock=14318180)

#use rs232(baud=9600, xmit=PIN_B7, rcv=PIN_B6, STREAM=PC_HOST)


// We'll set the I/O direction so we can just read/write I/O pins.
#use fast_io(A)
#use fast_io(B)
#use fast_io(C)


/**
 *  @defgroup led LED Driver
 *
 *  Drives the multiplex LED display.
 *
 *  @{
 */


// Map I/O pin names to hardware pins.

/// LED Digit 1 - Port B3
#define IO_LED_DIGIT_1 PIN_B3

/// LED Digit 2 - Port C5
#define IO_LED_DIGIT_2 PIN_C5

#define IO_LED_SEGMENT_B PIN_C0

#define IO_LED_SEGMENT_F PIN_B4

#define IO_LED_SEGMENT_G PIN_B5

#define IO_CLK PIN_C3
#define IO_DATA PIN_C4 



#define LED_COLON 0x01
#define LED_SEG_C 0x02
#define LED_SEG_D 0x04
#define LED_SEG_E 0x08

#define LED_SEG_B 0x10
#define LED_SEG_A 0x20
#define LED_SEG_F 0x40
#define LED_SEG_G 0x80

#define DIGIT_OFF 0x10

const uint8_t LED_SEG_ARRAY[] =
{
    // Digit 0
    LED_SEG_A | LED_SEG_B | LED_SEG_C | LED_SEG_D | LED_SEG_E | LED_SEG_F,

    // Digit 1
    LED_SEG_B | LED_SEG_C,

    // Digit 2
    LED_SEG_A | LED_SEG_B | LED_SEG_D | LED_SEG_E | LED_SEG_G,

    // Digit 3
    LED_SEG_A | LED_SEG_B | LED_SEG_C | LED_SEG_D | LED_SEG_G,

    // Digit 4
    LED_SEG_B | LED_SEG_C | LED_SEG_F | LED_SEG_G,

    // Digit 5
    LED_SEG_A | LED_SEG_C | LED_SEG_D | LED_SEG_F | LED_SEG_G,

    // Digit 6
    LED_SEG_A | LED_SEG_C | LED_SEG_D | LED_SEG_E | LED_SEG_F | LED_SEG_G,

    // Digit 7
    LED_SEG_A | LED_SEG_B | LED_SEG_C | LED_SEG_F,

    // Digit 8
    LED_SEG_A | LED_SEG_B | LED_SEG_C | LED_SEG_D | LED_SEG_E | LED_SEG_F | LED_SEG_G,

    // Digit 9
    LED_SEG_A | LED_SEG_B | LED_SEG_C | LED_SEG_D | LED_SEG_F | LED_SEG_G,

    // Digit A
    LED_SEG_A | LED_SEG_B | LED_SEG_C | LED_SEG_E | LED_SEG_F | LED_SEG_G,

    // Digit B
    LED_SEG_C | LED_SEG_D | LED_SEG_E | LED_SEG_F | LED_SEG_G,

    // Digit C
    LED_SEG_A | LED_SEG_D | LED_SEG_E | LED_SEG_F,

    // Digit D
    LED_SEG_B | LED_SEG_C | LED_SEG_D | LED_SEG_E | LED_SEG_G,

    // Digit E
    LED_SEG_A | LED_SEG_D | LED_SEG_E | LED_SEG_F | LED_SEG_G,

    // Digit F
    LED_SEG_A | LED_SEG_E | LED_SEG_F | LED_SEG_G,

    // 0x10 - All segments off
    0x00
};

uint8_t ledSegment1;

uint8_t ledSegment2;

/// 5mS clock rate
#define LED_PWM_RATE 576

uint16_t ledTimerCompare;

bool_t ledDigit1Flag;

/**
 *   Initialize the LED driver.
 */
void ledInit()
{
    ledSegment1 = 0x00;
    ledSegment2 = 0x00;

    ledDigit1Flag = false;

    ledTimerCompare = LED_PWM_RATE;

    CCP_1 = LED_PWM_RATE;
    set_timer1(ledTimerCompare);
    setup_ccp1( CCP_COMPARE_INT );
    setup_timer_1 (T1_INTERNAL | T1_DIV_BY_8);
}

uint8_t ledGetSegments (uint8_t digit)
{
    if (digit > sizeof(LED_SEG_ARRAY))
        return 0x00;

    return LED_SEG_ARRAY[digit];
}

void ledSetSegments (uint8_t segment1, uint8_t segment2)
{
    ledSegment1 = segment1;
    ledSegment2 = segment2;
}

void ledWriteSegments (uint8_t segments)
{
    output_a (segments & 0x2f);

    output_bit (IO_LED_SEGMENT_B, (segments & LED_SEG_B));
    output_bit (IO_LED_SEGMENT_F, (segments & LED_SEG_F));
    output_bit (IO_LED_SEGMENT_G, (segments & LED_SEG_G));
}

#INT_CCP1
void ledTimer()
{
    // Setup the next interrupt for the operational mode.
    ledTimerCompare += LED_PWM_RATE;
    CCP_1 = ledTimerCompare;

    if (ledDigit1Flag)
    {
        output_low (IO_LED_DIGIT_1);

        ledDigit1Flag = false;

        ledWriteSegments (ledSegment1);

        output_high (IO_LED_DIGIT_2);
    } else {
        output_low (IO_LED_DIGIT_2);

        ledDigit1Flag = true;

        ledWriteSegments (ledSegment2);

        output_high (IO_LED_DIGIT_1);
    } // END if-else
}


/** @} */


/**
 *  @defgroup sys System Library Functions
 *
 *  Generic system functions similiar to the C run-time library.
 *
 *  @{
 */

/**
 *   Initialize the system library and global resources.
 */
void sysInit()
{
    // Set all outputs low.
    output_a (0x00);
    output_b (0x00);
    output_c (0x00);
    
    // Configure the port direction (input/output).
    set_tris_a (0x10);
    set_tris_b (0x47);
    set_tris_c (0x1c);

    // Disable all ADC ports.
    setup_adc_ports (NO_ANALOGS);

    port_b_pullups (true);
}

/** @} */

/**
 *  @defgroup app Device application
 *
 *  Provides the main functionality for the device.
 *
 *  @{
 */

/**
 *   Initialize the application specific variables and required processor resources.
 */
void appInit()
{
}

uint8_t head;
uint8_t tail;
uint8_t buffer[256];

void writeSerial (uint8_t text)
{
    buffer[head] = text;

    ++head;
}

void serialUpdate ()
{
    if (head == tail)
        return;

    disable_interrupts (GLOBAL);
    fputc (buffer[tail], PC_HOST);
    enable_interrupts(GLOBAL);  

    ++tail;
}

unsigned char read_i2c(void);
void i2c_interrupt_handler(void);
void i2c_initialize(void);
void i2c_error(void);
void write_i2c(unsigned char transmit_byte); 


#define RX_BUF_LEN  4

unsigned char slave_buffer[RX_BUF_LEN];

int buffer_index;

#byte PIC_SSPBUF   = 0xfc9
#byte PIC_SSPADD   = 0xfc8
#byte PIC_SSPSTAT  = 0xfc7
#byte PIC_SSPCON1  = 0xfc6
#byte PIC_PIE1     = 0xf9d
#byte PIC_TRISC    = 0xf94

#byte PIC_SSPCON2  = 0xfc5 


/* Bit defines */
#define PIC_SSPSTAT_BIT_SMP     0x80
#define PIC_SSPSTAT_BIT_CKE     0x40
#define PIC_SSPSTAT_BIT_DA      0x20
#define PIC_SSPSTAT_BIT_P       0x10
#define PIC_SSPSTAT_BIT_S       0x08
#define PIC_SSPSTAT_BIT_RW      0x04
#define PIC_SSPSTAT_BIT_UA      0x02
#define PIC_SSPSTAT_BIT_BF      0x01

#define PIC_SSPCON1_BIT_WCOL    0x80
#define PIC_SSPCON1_BIT_SSPOV   0x40
#define PIC_SSPCON1_BIT_SSPEN   0x20
#define PIC_SSPCON1_BIT_CKP     0x10
#define PIC_SSPCON1_BIT_SSPM3   0x08
#define PIC_SSPCON1_BIT_SSPM2   0x04
#define PIC_SSPCON1_BIT_SSPM1   0x02
#define PIC_SSPCON1_BIT_SSPM0   0x01

#define PIC_SSPCON2_BIT_GCEN    0x80
#define PIC_SSPCON2_BIT_ACKSTAT 0x40
#define PIC_SSPCON2_BIT_ACKDT   0x20
#define PIC_SSPCON2_BIT_ACKEN   0x10
#define PIC_SSPCON2_BIT_RCEN    0x08
#define PIC_SSPCON2_BIT_PEN     0x04
#define PIC_SSPCON2_BIT_RSEN    0x02
#define PIC_SSPCON2_BIT_SEN     0x01 


bool_t readyFlag = false;

uint8_t data[2];

#INT_SSP
void ssp_interupt ()
{
    unsigned char temp_sspstat;
    unsigned char this_byte;
   
    /* Mask out the unnecessary bits */
    temp_sspstat = PIC_SSPSTAT & 0x2D;
   

    switch (temp_sspstat)
    {
        // Write operation, last byte was an address, buffer is full
        case 0x09:
            // Reset the buffer pointer.
            buffer_index = 0;

            // Dummy ready of buffer.
            this_byte = read_i2c();
            break;
       
            // Write operation, last byte was data, buffer is full
        case 0x29:
            // Read the byte.
            this_byte = read_i2c();

            slave_buffer[buffer_index] = this_byte;

            if (buffer_index != RX_BUF_LEN)
                ++buffer_index;


            if (buffer_index == 2)
            {
                data[0] = slave_buffer[0];
                data[1] = slave_buffer[1];
                readyFlag = true;
            }

          break;
       
       
    default:
      break;
    }

}

/* This function returns the byte in SSPBUF */
unsigned char read_i2c(void)
{
    return PIC_SSPBUF;
}


uint8_t appGetAddress()
{
    if (input(PIN_B1) == 0)
        return 0x40;

    if (input(PIN_B2) == 0)
        return 0x42;
}


void appRun(uint8_t address)
{
    head = 0;
    tail = 0;

    ledSetSegments (ledGetSegments(0x0a), ledGetSegments(0x0c));


    while (PIC_SSPCON2 & 0x1f);
     
    // Clear the SSPSTAT register.
    PIC_SSPSTAT = 0x00;
    PIC_SSPCON1 = 0x36;

    PIC_SSPADD = address;



    enable_interrupts(INT_SSP);
    enable_interrupts(INT_CCP1);
    enable_interrupts(GLOBAL);


    for (;;)
    {
        if (readyFlag)
        {
            readyFlag = false;
            ledSetSegments (data[0], data[1]);
        } 
    }
}

/** @} */

/// Function where everything gets started.
void main()
{
    // Configure the basic system.
    sysInit();

    // Wait for the power converter chains to stabilize.
    delay_ms (100);

    // Setup the subsystems.
    appInit();
    ledInit();

	// Run the end application.
    appRun(appGetAddress());
}