• 用C语言提交到这里的勇士，交个朋友：840152826；附加信息：吉大辣鸡

---

• 似乎是累计计数实验

/*
 * Exp_10: interupt
 * author: liu abin
 * all right reserved
 **/
#include "conio.h"
#include "dos.h"
typedef unsigned char u8;
typedef unsigned int u16;

// 8254
u16 M8254_0 = 0x0680;
u16 M8254_1 = 0x0682;
u16 M8254_SET = 0x0686;
u8 cmd_8254 = 0x36;
u8 freq_h = 0x03;
u8 freq_l = 0x0e8;
// 8255
u16 M8255_SET = 0x0606;
u16 M8255_A = 0x0600;
u16 M8255_B = 0x0602;
u8 cmd_8255 = 0x80;
// subfunc
void exit(void);
//void delay(u16 time);
void init8254(void);
void interrupt far interp(void);
// global var
u16 count = 0x00;
u16 temp = 0x01;

void main() {
	init8254();
	__asm {
		MOV AX, OFFSET interp
		MOV SI, 0038H
		MOV [ES:SI], AX
		MOV AX, CS
		MOV SI, 003AH
		MOV [ES:SI], AX
		CLI
		MOV AL,11H  // ICW1
		OUT 20H, AL
		MOV AL, 08H  // ICW2 
		OUT 21H, AL
		MOV AL, 04H  // ICW3
		OUT 21H, AL
		MOV AL, 03H  // ICW4
		OUT 21H, AL
		MOV AL, 00H  // OCW1 //NO MASK
		OUT 21H, AL
		STI
	}
	while(1) {
		outportb(M8255_B, (u8)temp);
		outportb(M8255_A, (u8)count);
		delay(10000);
	}
	exit();
}

void exit() {
	__asm{
		MOV AH,4CH
		INT 21H
	}
}

void delay(u16 time) {
	int i = 0,j=0;
	for(;i<time;i++) {
		for(;j<10000;j++)
			;
	}
}

void init8254() {
	outportb(M8254_SET, cmd_8254);
	outportb(M8254_0, freq_l);
	outportb(M8254_0, freq_h);
	outportb(M8254_SET, 0x76);
	outportb(M8254_1, freq_l);
	outportb(M8254_1, freq_h);
	outportb(M8255_SET, cmd_8255);
}

void interrupt interp() {
	count++;
	temp = count>>8;
	/*__asm {
		MOV AH,4CH
		INT 21H
	}*/
	return;
}