//-----------------------------------------------------------------------------
// Note
//  タイマー0を使用してRA2のLEDを点滅させる
//  PICの周波数を32Mhzに設定
//-----------------------------------------------------------------------------
#include <xc.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>


// コンフィグレーションBIT1 設定
#pragma config FOSC = INTOSC    // Oscillator Selection (INTOSC oscillator: I/O function on CLKIN pin)
#pragma config WDTE = OFF       // Watchdog Timer Enable (WDT disabled)
#pragma config PWRTE = ON       // Power-up Timer Enable (PWRT enabled)
#pragma config MCLRE = OFF      // MCLR Pin Function Select (MCLR/VPP pin function is MCLR)
#pragma config CP = OFF         // Flash Program Memory Code Protection (Program memory code protection is disabled)
#pragma config CPD = OFF        // Data Memory Code Protection (Data memory code protection is disabled)
#pragma config BOREN = OFF      // Brown-out Reset Enable (Brown-out Reset disabled)
#pragma config CLKOUTEN = OFF   // Clock Out Enable (CLKOUT function is disabled. I/O or oscillator function on the CLKOUT pin)
#pragma config IESO = OFF       // Internal/External Switchover (Internal/External Switchover mode is disabled)
#pragma config FCMEN = OFF      // Fail-Safe Clock Monitor Enable (Fail-Safe Clock Monitor is disabled)

// コンフィグレーションBIT2 設定
#pragma config WRT = OFF        // Flash Memory Self-Write Protection (Write protection off)
#pragma config PLLEN = ON       // PLL Enable (4x PLL enabled)
#pragma config STVREN = ON      // Stack Overflow/Underflow Reset Enable (Stack Overflow or Underflow will cause a Reset)
#pragma config BORV = HI        // Brown-out Reset Voltage Selection (Brown-out Reset Voltage (Vbor), high trip point selected.)
#pragma config LVP = OFF        // Low-Voltage Programming Enable (High-voltage on MCLR/VPP must be used for programming)


bool  g_led_flg = false;
unsigned short time_cnt = 0;


// タイマ0割り込み処理
// 100μsec毎に割り込み発生
void interrupt time0( void )
{
    if( TMR0IF )
    {
        time_cnt++;
        if( time_cnt >= 10000 )
        {
            g_led_flg = ~g_led_flg; // 反転
            time_cnt = 0;
        }

        TMR0 = 156; // 初期カウンタ再設定
        TMR0IF = 0; // タイマ割り込みフラグをクリアする
    }
}


int main(int argc, char** argv)
{
    OSCCON = 0b01110000 ;    // 内部クロック8ＭＨｚ

    ANSELA = 0b00000000 ;    // すべてデジタルI/Oに割当てる
    TRISA  = 0b00001000 ;    // RA3を入力とする
    PORTA  = 0b00000000 ;    // ピン状態初期化

    OPTION_REG = 0b00000010 ;// 0-2bitでタイマ0のクロックを1/8に設定
    TMR0 = 156;              // 初期カウンタ設定
    TMR0IF = 0;              // タイマ割り込みフラグ初期化
    TMR0IE = 1;              // タイマ割り込み有効
    GIE = 1;                 // 全割り込み有効

    for(;;)
    {
        if( g_led_flg )
        {
            RA2 = 1;
        }
        else
        {
            RA2 = 0;
        }
    }

    return (EXIT_SUCCESS);
}