isr.cpp

关于ETR100的设计

#include <dos.h>
#include "isr.h"

#ifdef __cplusplus
    #define __CPPARGS ...
#else
    #define __CPPARGS
#endif

#define IRQ2MaskBit	0x04
#define IRQ7MaskBit	0x80
#define IRQ9MaskBit	0x02
#define IRQ11MaskBit	0x08

unsigned int IRQ7cnt;
unsigned int IRQ9cnt;
unsigned int IRQ11cnt;

void interrupt ( *oldIRQ7handler)(__CPPARGS);
void interrupt ( *oldIRQ9handler)(__CPPARGS);
void interrupt ( *oldIRQ11handler)(__CPPARGS);

void interrupt IRQ7_ISR(__CPPARGS);
void interrupt IRQ9_ISR(__CPPARGS);
void interrupt IRQ11_ISR(__CPPARGS);

void interrupt IRQ7_ISR(__CPPARGS)
{
   enable( );

   // put your code here
   IRQ7cnt++;

   //send EOI
   outportb( 0x20, 0x67 );	// specific EOI command
}

void interrupt IRQ9_ISR(__CPPARGS)
{
   enable( );

   // put your code here
   IRQ9cnt++;

   //send EOI
   outportb( 0xa0, 0x61 );
   outportb( 0x20, 0x62 );
}


void interrupt IRQ11_ISR(__CPPARGS)
{
   enable( );

   // put your code here
   IRQ11cnt++;

   //send EOI
   outportb( 0xa0, 0x63 );
   outportb( 0x20, 0x62 );
}

/*///////////////////////////////////////////////
   INPUT: intno => interrupt number in software

	ISA NAME	intno
    ------------------------------
	  IRQ7     |     0x0f
	  IRQ9     |     0x71
	  IRQ11    |     0x73
///////////////////////////////////////////////*/
int InstallISR( int intno )
{
   unsigned char MaskBit;

   switch( intno )
      {

      case 0x0f:
	   MaskBit = IRQ7MaskBit;
	   outportb( 0x21, inportb(0x21)|MaskBit );	// mask irq7
	   oldIRQ7handler = getvect( intno );
	   setvect( intno, IRQ7_ISR );
	   MaskBit = ~MaskBit;
	   outportb( 0x21, inportb(0x21)&MaskBit );	// unmask irq7
	   break;

      case 0x71:
	   MaskBit = IRQ9MaskBit;
	   outportb( 0xa1, inportb(0xa1)|MaskBit );	// mask irq9
	   oldIRQ9handler = getvect( intno );
	   setvect( intno, IRQ9_ISR );
	   MaskBit = ~MaskBit;
	   outportb( 0xa1, inportb(0xa1)&MaskBit );	// unmask irq9
	   MaskBit = ~IRQ2MaskBit;
	   outportb( 0x21, inportb(0x21)&MaskBit );	// unmask irq2
	   break;

      case 0x73:
	   MaskBit = IRQ11MaskBit;
	   outportb( 0xa1, inportb(0xa1)|MaskBit );	// mask irq11
	   oldIRQ11handler = getvect( intno );
	   setvect( intno, IRQ11_ISR );
	   MaskBit = ~MaskBit;
	   outportb( 0xa1, inportb(0xa1)&MaskBit );	// unmask irq11
	   MaskBit = ~IRQ2MaskBit;
	   outportb( 0x21, inportb(0x21)&MaskBit );	// unmask irq2
	   break;

      default:
	   return -1;
      }

   return 0;
}

int UninstallISR( int intno )
{
   unsigned char MaskBit;

   switch( intno )
      {
      case 0x0f:
	   MaskBit = IRQ7MaskBit;
	   outportb( 0x21, inportb(0x21)|MaskBit );	// mask irq7
	   setvect( intno, oldIRQ7handler );
	   break;

      case 0x71:
	   MaskBit = IRQ9MaskBit;
	   outportb( 0xa1, inportb(0xa1)|MaskBit );	// mask irq9
	   setvect( intno, oldIRQ9handler );
	   break;

      case 0x73:
	   MaskBit = IRQ11MaskBit;
	   outportb( 0xa1, inportb(0xa1)|MaskBit );	// mask irq11
	   setvect( intno, oldIRQ11handler );
	   break;

      default:
	   return -1;
      }

   return 0;
}