vm51_intr.c

c51 单片机模拟器C++文件格式元代纳一边以

/*
  Name: VM51_intr
  Copyright: 2005
  Author: rockins
  Date: 15-08-05 21:39
  Description: check whether interrupt occupy or not
*/

#include "VM51.h"
#include <stdio.h>
#include <stdlib.h>

static int int0_intr(void);
static int int1_intr(void);
static int t0_intr(void);
static int t1_intr(void);
static int s_intr(void);

/*****************************
 INTR PRECEDENCE ORDER:
     EX0		--IE0
     T0			--TF0
     EX1		--IE1
     T1			--TF1
     SERIES		--RI or TI
 *******************************/
int VM51_intr(void)
{
    if (!GET_EA)			// close intr,just return
        return;
        
    // FIRST LEVEL INTR
    if (GET_EX0 && GET_PX0 && GET_IE0){
        int0_intr();
        return 0;
    }
    else if (GET_ET0 && GET_PT0 && GET_IT0){
    	t0_intr();
    	return 0;
    }
    else if (GET_EX1 && GET_PX1 && GET_IE1){
    	int1_intr();
    	return 0;
    }
    else if (GET_ET1 && GET_PT1 && GET_IT1){
    	t1_intr();
    	return 0;
    }
    else if (GET_ES && GET_PS && (GET_TI || GET_RI)){
    	s_intr();
    	return 0;
    }
        
    // SECONDARY LEVEL INTR,IGNORE PRECEDENCE BIT    
    if (GET_EX0 && !GET_PX0 && GET_IE0){
        int0_intr();
        return 0;
    }
    else if(GET_ET0 && !GET_PT0 && GET_IT0){
        t0_intr();
    	return 0;
    }
    else if(GET_EX1 && !GET_PX1 && GET_IE1){
        int1_intr();
    	return 0;
    }
    else if(GET_ET1 && !GET_PT1 && GET_IT1){
        t1_intr();
    	return 0;
    }
    else if(GET_ES && !GET_PS && (GET_TI || GET_RI)){
        s_intr();
    	return 0;
    }
}

static int int0_intr(void)
{
    U8	temp;
    
    temp = (U8)(PC&0x00FF);
    SP += 1;
    RAM[SP] = temp;
    temp = (U8)(PC&0xFF00);
    SP += 1;
    RAM[SP] =temp;
    
    PC = (U16)0x0003;
}

static int int1_intr(void)
{
    U8	temp;
    
    temp = (U8)(PC&0x00FF);
    SP += 1;
    RAM[SP] = temp;
    temp = (U8)(PC&0xFF00);
    SP += 1;
    RAM[SP] =temp;
    
    PC = (U16)0x0013;
}

static int t0_intr(void)
{
    U8	temp;
    
    temp = (U8)(PC&0x00FF);
    SP += 1;
    RAM[SP] = temp;
    temp = (U8)(PC&0xFF00);
    SP += 1;
    RAM[SP] =temp;
    
    PC = (U16)0x000B;
}

static int t1_intr(void)
{
    U8	temp;
    
    temp = (U8)(PC&0x00FF);
    SP += 1;
    RAM[SP] = temp;
    temp = (U8)(PC&0xFF00);
    SP += 1;
    RAM[SP] =temp;
    
    PC = (U16)0x001B;
}

static int s_intr(void)
{
    U8	temp;
    
    temp = (U8)(PC&0x00FF);
    SP += 1;
    RAM[SP] = temp;
    temp = (U8)(PC&0xFF00);
    SP += 1;
    RAM[SP] =temp;
    
    PC = (U16)0x0023;
}