PIC18F27Q43 外部ピン割込み Interrupt On Change

# Q43の外部スイッチ割込み　
![IMG_4691.JPG](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/3693934/23736ae5-70a7-4323-7505-f7116712fdd7.jpeg)

**外部のスイッチで、割込みを発生させる設定方法です。**

# １．割込みピンの割り付け可能ポート
![availability per Device.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/3693934/0f8bcde9-21c2-5906-7a61-49b41b973b8c.png)

:::note info
18F27Q43は、２８ピンなので、PORTA、PORTB、PORTCに割り付けることができます。
:::

# ２．Interrupt On Change Block Diaglam
![IOCdiaglam.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/3693934/b2c0f97b-1ef3-af47-3eda-68eb40779eeb.png)

:::note
２－１.モジュールを有効にする。`IOCIE`ビットをセット。これで、個別割込みが許可されます。
```C:Q_Peripheral.c
    PIE0bits.IOCIE=1;//IOC割込み許可
    PIR0bits.IOCIF=0;//IOC割込みフラグ
```
:::
:::note
２－２.個別の割込みピン設定
**立ち上がり検出：`IOCxP`レジスタ**
![IOCxP.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/3693934/4dc02376-5ebc-7d02-8f54-8defe8172294.png)
ex.)RA3ピンを立ち上がり割込みピンとして指定。
```C
IOCAPbits.IOCAP3 = 1; //RA3 立ち上がりIOC割込みピン設定
```


**立ち下がり検出：`IOCxN`レジスタ**
![IOCxN.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/3693934/494d0caf-531d-52e9-2e50-f05e9744a668.png)
ex.)RC0ピンを立ち下がり割込みピンとして指定。
```C
IOCCNbits.IOCCN0 = 1; //RC0 立下りIOC割込みピン設定
```
:::

:::note 
２－３.個別の割込みフラグの処理
割り込み処理関数実行中に、検出された状態変化のビットデータが失われないように、XORとANDを組み合わせて、取りこぼしを防止しながら、該当ビットをクリアして、関数を終了させます。
|XOR|0|1|                  
|:----:|:----:|:----:|
|0|0|1|
|1|1|0|

ex)RC0割込みが発生し、処理が終わって割り込みフラグをクリアする方法
![取りこぼし防止.jpg](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/3693934/3e051042-a1b3-7b2e-3a47-617b3ed18900.jpeg)

関数の最初で、XORで、実行先頭の状態を保持し、処理がおわり、該当フラグをクリアするとき、割り込み実行中の状態変化をANDで、取り込んでいます。
:::

# ４．IOC割込みコード
```C:Q_Peripheral.h

#ifndef Q_PERIPHERAL27Q43_H
#define	Q_PERIPHERAL27Q43_H

#ifdef	__cplusplus
extern "C" {
#endif

#include <xc.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
    
#define Low 0
#define High 1
   
#define _XTAL_FREQ 32000000
#define BAUDRATE 115200
#define SET_SPBRG_DATA  (((unsigned int)((_XTAL_FREQ/4)/BAUDRATE))-1)
#define SET_SPBRG_DATA1 (((unsigned int)((_XTAL_FREQ/16)/BAUDRATE))-1)   
//USART---------------------------------------
#define RXUSART_BUFFER_SIZE 20
typedef struct
{
    uint8_t buf[RXUSART_BUFFER_SIZE];
    uint8_t length;
    uint8_t completed;
}_rxUsart;
extern _rxUsart rxUsart;
extern void usartInit(void);
extern void putch(uint8_t);
extern uint8_t getch(void);
//Timer--------------------------------------
typedef struct
{
    uint16_t cnt;
    bool fg;
}_tm;
extern _tm tm0,tm2;
extern void timer0Init(void);    
extern void timer2Init(void);
//IOC------------------------------------------
extern void iocInit(void);
typedef struct
{
    bool fg;
}_ioc;
extern _ioc ioc;  

#ifdef	__cplusplus
}
#endif

#endif	/* Q_PERIPHERAL27Q43_H */


```
```C:Q_Peripheral.c

#include <pic18f27q43.h>
#include "Q_peripheral27Q43.h"

//*****************************************************//
//Timer0初期化
//*****************************************************//
_rxUsart rxUsart;
void usartInit(void)
{
    //1.ボーレート設定115200
    U1BRG=SET_SPBRG_DATA1;
    //2.モード　非同期
    U1CON0bits.MODE=0b0000; //Asynchronous 8-bit USART mode
    //4.Serial port enabled
    U1CON1bits.ON=1;
    //5.Transmit is enabled.
    U1CON0bits.TXEN=1;
    U1CON0bits.RXEN=1;
    //6.PPS
    PPSLOCK = 0x55; 
    PPSLOCK = 0xAA;
    PPSLOCKbits.PPSLOCKED = 0;//Unlock.
    U1RXPPS=0b010111;//RC7:rx
    RC6PPS=0x20;//RC6:tx
    TRISC|=0x80;
    PPSLOCK = 0x55; 
    PPSLOCK = 0xAA;
    PPSLOCKbits.PPSLOCKED = 1;//lock.
    //7.interrupt
    PIR4bits.U1RXIF=0;
    PIE4bits.U1RXIE=1; 
}

void putch(uint8_t _txData)
{
    if(U1ERRIRbits.TXMTIF==High)//ｼﾌﾄﾚｼﾞｽﾀ空?
    {
        do{
            U1TXB=_txData;
            while(U1ERRIRbits.TXMTIF==Low);
        }while(U1FIFObits.TXBF);//TXﾊﾞｯﾌｧ空になるまで送信。
    }else{
        //error operation
    }
}

uint8_t getch(void)
{
    while(PIR4bits.U1RXIF==Low);//受信完了
    return U1RXB;
}

//*****************************************************//
//Timer0初期化
//*****************************************************//
_tm tm0;
void timer0Init(void)
{
//Timer0初期化--------------------------------------------------
    T0CON1bits.CS=0b010;//クロックソースFosc/4
    T0CON1bits.CKPS=0b0011;//プリスケ1:8
    T0CON0bits.MD16=1;//16bitsタイマー
    T0CON0bits.OUTPS=0b0000;//ﾎﾟｽﾄｽｹｰﾗ1:1
    TMR0H=0xD8;//10ms Fosc=32Mhz
    TMR0L=0xF0;//10ms 
    T0CON0bits.EN=1;
    PIE3bits.TMR0IE=1;
    PIR3bits.TMR0IF=0;
}

//*****************************************************//
//IOC Interrupt On Change 初期化
//*****************************************************//
_ioc ioc;
void iocInit(void)
{
    IOCCNbits.IOCCN0=1;//RC0:立下り検出設定
    TRISC|=0x01;       //RC0:入力ピン
    PIE0bits.IOCIE=1;　//外部割込み許可
    PIR0bits.IOCIF=0;  //外部割込みフラグクリア
}

```
```Q_interrupt.h
#ifndef Q_INTERRUPT_H
#define	Q_INTERRUPT_H

#ifdef	__cplusplus
extern "C" {
#endif

#include <xc.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
#include "Q_peripheral27Q43.h"
  
extern void __interrupt(irq(IRQ_U1RX)) USART1RX_ISR(void);    
extern void __interrupt(irq(IRQ_TMR0)) Timer0_ISR(void); 
extern extern void __interrupt(irq(IRQ_TMR2)) Timer2_ISR(void); 
extern void __interrupt(irq(IRQ_IOC)) IOC_ISR(void);

#ifdef	__cplusplus
}
#endif

#endif	/* Q_INTERRUPT_H */
```
```C:
#include "Q_interrupt27Q43.h"

//****************割り込み関数***********************//
// USART1割込み
//**************************************************//
void __interrupt(irq(IRQ_U1RX)) USART1RX_ISR(void)
{
    uint8_t ch;
    PIR4bits.U1RXIF=0;
    ch=getch();
    rxUsart.buf[rxUsart.length++]=ch;
    if(rxUsart.length>RXUSART_BUFFER_SIZE)
    {
        rxUsart.length=0;
    }
    if(ch==0x0a)
    {
        rxUsart.buf[rxUsart.length-2]=0x00;
        PIE4bits.U1RXIE=0;
        rxUsart.completed=1;
    }
}

//****************割り込み関数***********************//
// Timer0割込み
//**************************************************//
void __interrupt(irq(IRQ_TMR0)) Timer0_ISR(void)
{
    PIR3bits.TMR0IF=0;
    tm0.cnt++;
    if(tm0.cnt==50)
    {
        tm0.cnt=0;
        tm0.fg=true;
        T0CON0bits.EN=0;
        PIE3bits.TMR0IE=0;
    }
    
    TMR0L=0xF0;//10ms
}

//****************割り込み関数***********************//
// IOC割込み
// ※印は、割り込み関数実行中の変化を取りこぼさないためのコード。
//**************************************************//
void __interrupt(irq(IRQ_IOC)) IOC_ISR(void)
{
    uint8_t val,mask;
    
    PIR0bits.IOCIF=0;
    val=IOCCF;  //※IOCフラグレジスタ読み出し
    mask=0xFF;  //※ゼロクリアマスク
    mask=mask^val;//※現状を記録
    if(IOCCNbits.IOCCN0==1 && val==0x01)
    {
        ioc.fg=true; //main関数で実処理開始
        PIE0bits.IOCIE=0;//一時割り込み停止
    }
    //zero clear--------------    
    IOCCF&=mask;   //※状態変化の取りこぼしをしない。
}


```




```main.c
// PIC18F27Q43 Configuration Bit Settings

// 'C' source line config statements

// CONFIG1
#pragma config FEXTOSC = OFF    // External Oscillator Selection (Oscillator not enabled)
#pragma config RSTOSC = HFINTOSC_64MHZ// Reset Oscillator Selection (HFINTOSC with HFFRQ = 64 MHz and CDIV = 1:1)

// CONFIG2
#pragma config CLKOUTEN = OFF   // Clock out Enable bit (CLKOUT function is disabled)
#pragma config PR1WAY = OFF     // PRLOCKED One-Way Set Enable bit (PRLOCKED bit can be set and cleared repeatedly)
#pragma config CSWEN = ON       // Clock Switch Enable bit (Writing to NOSC and NDIV is allowed)
#pragma config FCMEN = OFF      // Fail-Safe Clock Monitor Enable bit (Fail-Safe Clock Monitor disabled)

// CONFIG3
#pragma config MCLRE = EXTMCLR  // MCLR Enable bit (If LVP = 0, MCLR pin is MCLR; If LVP = 1, RE3 pin function is MCLR )
#pragma config PWRTS = PWRT_OFF // Power-up timer selection bits (PWRT is disabled)
#pragma config MVECEN = ON      // Multi-vector enable bit (Multi-vector enabled, Vector table used for interrupts)
#pragma config IVT1WAY = ON     // IVTLOCK bit One-way set enable bit (IVTLOCKED bit can be cleared and set only once)
#pragma config LPBOREN = OFF    // Low Power BOR Enable bit (Low-Power BOR disabled)
#pragma config BOREN = SBORDIS  // Brown-out Reset Enable bits (Brown-out Reset enabled , SBOREN bit is ignored)

// CONFIG4
#pragma config BORV = VBOR_1P9  // Brown-out Reset Voltage Selection bits (Brown-out Reset Voltage (VBOR) set to 1.9V)
#pragma config ZCD = OFF        // ZCD Disable bit (ZCD module is disabled. ZCD can be enabled by setting the ZCDSEN bit of ZCDCON)
#pragma config PPS1WAY = OFF     // PPSLOCK bit One-Way Set Enable bit (PPSLOCKED bit can be cleared and set only once; PPS registers remain locked after one clear/set cycle)
#pragma config STVREN = ON      // Stack Full/Underflow Reset Enable bit (Stack full/underflow will cause Reset)
#pragma config LVP = ON         // Low Voltage Programming Enable bit (Low voltage programming enabled. MCLR/VPP pin function is MCLR. MCLRE configuration bit is ignored)
#pragma config XINST = OFF      // Extended Instruction Set Enable bit (Extended Instruction Set and Indexed Addressing Mode disabled)

// CONFIG5
#pragma config WDTCPS = WDTCPS_31// WDT Period selection bits (Divider ratio 1:65536; software control of WDTPS)
#pragma config WDTE = OFF       // WDT operating mode (WDT Disabled; SWDTEN is ignored)

// CONFIG6
#pragma config WDTCWS = WDTCWS_7// WDT Window Select bits (window always open (100%); software control; keyed access not required)
#pragma config WDTCCS = SC      // WDT input clock selector (Software Control)

// CONFIG7
#pragma config BBSIZE = BBSIZE_512// Boot Block Size selection bits (Boot Block size is 512 words)
#pragma config BBEN = OFF       // Boot Block enable bit (Boot block disabled)
#pragma config SAFEN = OFF      // Storage Area Flash enable bit (SAF disabled)
#pragma config DEBUG = OFF      // Background Debugger (Background Debugger disabled)

// CONFIG8
#pragma config WRTB = OFF       // Boot Block Write Protection bit (Boot Block not Write protected)
#pragma config WRTC = OFF       // Configuration Register Write Protection bit (Configuration registers not Write protected)
#pragma config WRTD = OFF       // Data EEPROM Write Protection bit (Data EEPROM not Write protected)
#pragma config WRTSAF = OFF     // SAF Write protection bit (SAF not Write Protected)
#pragma config WRTAPP = OFF     // Application Block write protection bit (Application Block not write protected)

// CONFIG10
#pragma config CP = OFF         // PFM and Data EEPROM Code Protection bit (PFM and Data EEPROM code protection disabled)

// #pragma config statements should precede project file includes.
// Use project enums instead of #define for ON and OFF.

#include <xc.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdbool.h>
#include "Q_peripheral27Q43.h"
#include "Q_interrupt27Q43.h"
#include "Q_initialize.h"
#include "Q_I2C1.h"
#include "I2C_LCD.h"
#include "stringFormat.h"

void portInit(void);
void oscillatorInit(void);
void vicInit(void);

void main(void)
{
    uint8_t counter=0;
    //CPUハード初期化-----------------------
    portInit();
    oscillatorInit();
    vicInit();
    
    //周辺機能初期化--------------------------------
    timer0Init();
    iocInit();
    usartInit();
    printf("START Interrupt On Change\n");    
    I2C1_Init();    
    INTCON0bits.GIE=1;//Enable all masked interrupts
    
    while(1)
    {
        //Timer0 interrupt-------
        if(tm0.fg)
        {
            tm0.fg=false;
            PORTBbits.RB0=~PORTBbits.RB0;
            T0CON0bits.EN=1;
            PIE3bits.TMR0IE=1;
        } 
        
        //Interrupt On Change Interrupt--------
        if(ioc.fg)
        {
            ioc.fg=false;
            printf("Switch ON:%d\n",counter);
            PORTBbits.RB1=~PORTBbits.RB1;
            counter++;
            PIE0bits.IOCIE=1;
        }
    }
    return;
}

void oscillatorInit(void)
{
    //オシレータ設定----------------
    OSCCON3bits.CSWHOLD=1;//Hold
    OSCCON1bits.NDIV=1;//64Mhz/2=32Mhz;
    while(!OSCCON3bits.NOSCR);
    while(!PIR0bits.CSWIF);//ready state
    PIR0bits.CSWIF=0;
    OSCCON3bits.CSWHOLD=0;
    while(!OSCCON3bits.ORDY);
}

void portInit(void)
{
    //ポート設定----------------------    
    PORTA=0x00;
    LATA=0x00;
    ANSELA=0x00;
    TRISA=0x00;
    
    PORTB=0x00;
    LATB=0x00;
    ANSELB=0x00;
    TRISB=0x00;
    
    PORTC=0x00;
    LATC=0x00;
    ANSELC=0x00;
    TRISC=0x00;
}

void vicInit(void)
{
 //割り込みテーブルaddress設定----------------------------------
    INTCON0bits.GIE=0;//Enable all masked interrupts
    IVTLOCK=0x55;
    IVTLOCK=0xAA;
    IVTLOCKbits.IVTLOCKED=0;
    IVTBASE = 0x000008;
    IVTLOCK=0x55;
    IVTLOCK=0xAA;
    IVTLOCKbits.IVTLOCKED=1;
}
```