/*******************************************************************/
/* Advanced Communication Board Developer Toolkit 1993		   */
/*   For use with Advanced Communication Boards 		   */
/*  INT.C                                                          */
/*  This file defines routines that setup interrupt handling.      */
/*                                                                 */
/*  Source file is INT.C                                           */
/* .OBJ File Linked to Program for interrupt use                   */
/*******************************************************************/
#include <stdio.h>
#include <conio.h>
#include <bios.h>
#include <dos.h>
#include <stddef.h>
#include <string.h>
#include "int.h"



/*******************************************************************
    Stuff to make us "compiler friendly"
 *******************************************************************/
#ifdef _BORLAND
        #define FAR             far
        #define INTERRUPT       far interrupt
        #define IN              inportb
        #define OUT             outportb
	#define GETVECT		getvect
	#define SETVECT         setvect
#else
        #define FAR             _far
        #define INTERRUPT       __far __interrupt
        #define IN              _inp
	#define OUT             _outp
	#define GETVECT		_dos_getvect
	#define SETVECT		_dos_setvect
#endif



/*******************************************************************
    Stuff for IRQ Setup Routines
 *******************************************************************/
unsigned char	XT_PIC_MASK;
unsigned char	AT_PIC_MASK;
VOIDINTPROC	OldIRQVector;



/*******************************************************************
    IRQSetup	:
 This routine will replace the specified Interrupt Vector and setup
 the XT and AT PIC.
 *******************************************************************/
void IRQSetup(unsigned char bIRQ, VOIDINTPROC fpISR)
{
   unsigned char bNumber;

   if(bIRQ < 8) 		    /* Setup the IRQ Vector*/
	bNumber = 0x08 + bIRQ;	/* i.e IRQ2 = 0x0a*/
   else
	bNumber = 0x68 + bIRQ;	/* i.e IRQ9 = 0x71*/

   OldIRQVector = GETVECT(bNumber);
   SETVECT(bNumber, (VOIDINTPROC) fpISR);

   if(bIRQ < 8)
	{bNumber = 0x01 << bIRQ;
	 OUT(0x21, (~bNumber & IN(0x21)));
	}
   else
	{OUT(0x21,( 0xfb & IN(0x21)));	/*mask IRQ2*/
	 bNumber = 0x01 << (bIRQ - 8);
	 OUT(0xA1, (~bNumber & IN(0xA1)));
	}
}



/*******************************************************************
    IRQUnsetup   :
 This routine will restore the specified Interrupt Vector and restore
 the XT and AT PIC.
 *******************************************************************/
void IRQUnsetup(unsigned char bIRQ)
{
    unsigned char bNumber;

   /* Setup the IRQ Vector*/
   if(bIRQ < 8)
	bNumber = 0x08 + bIRQ;	/* i.e IRQ2 = 0x0a*/
   else
	bNumber = 0x68 + bIRQ;	/* i.e IRQ9 = 0x71*/

   SETVECT(bNumber, OldIRQVector);

    return;
}



/*******************************************************************
    SaveIRQMask	:
 This routine will save the contents of the PIC mask register
 *******************************************************************/
void SaveIRQMask (void)
{
   XT_PIC_MASK = (unsigned char) IN( 0x21);  /*Save the PIC Mask*/
   AT_PIC_MASK = (unsigned char) IN( 0xA1);
}  /* SaveIRQMask */



/*******************************************************************
    ReturnIRQMask :
 This routine will restore the contents of the PIC mask register
 *******************************************************************/
void ReturnIRQMask (void)
{
   /*Restore the PIC Mask*/
   OUT(0x21, XT_PIC_MASK);
   OUT(0xA1, AT_PIC_MASK);
}  /* ReturnIRQMask */