/* DEMO4 : INT_CHAN_1, timer interrupt demo (initial low)         */
/*         (It is designed to be a machine independent timer)     */
/* step1 : Run DEMO4.EXE                                          */
/* -------------------------------------------------------------- */
#include "PIO.H"

#define A1_8259 0x20
#define A2_8259 0xA0
#define EOI     0x20

static void interrupt irq_service();
void pio_da16_c0(char cConfig, char cLow, char cHigh);
void pio_da16_c1(char cConfig, char cLow, char cHigh);
void pio_da16_c2(char cConfig, char cLow, char cHigh);
void init_int1_low();

WORD wBase,wIrq;
int  COUNT_L,COUNT_H,irqmask,now_int_state;

int main()
{
int   i,j;
WORD  wBoards,wRetVal,t1,t2,t3,t4,t5,t6;
WORD  wSubVendor,wSubDevice,wSubAux,wSlotBus,wSlotDevice;

clrscr();

/* step1 : find address-mapping of PIO/PISO cards                 */
wRetVal=PIO_DriverInit(&wBoards,0x80,0x04,0x00);/*for PIO-DA16/8/4*/
printf("\n(1) Threr are %d PIO-DA16/8/4 Cards in this PC",wBoards);
if ( wBoards==0 )  exit(0);

printf("\n\n-------------- The Configuration Space --------------");
for(i=0;i<wBoards;i++)
   {
   PIO_GetConfigAddressSpace(i,&wBase,&wIrq,&wSubVendor,&wSubDevice,&wSubAux,&wSlotBus,&wSlotDevice);

   printf("\nCard_%d: wBase=%x,wIrq=%x,subID=[%x,%x,%x],SlotID=[%x,%x]",i,wBase,wIrq,wSubVendor,wSubDevice,wSubAux,wSlotBus,wSlotDevice);

   printf(" --> ");
   ShowPioPiso(wSubVendor,wSubDevice,wSubAux);
   }

PIO_GetConfigAddressSpace(0,&wBase,&wIrq,&t1,&t2,&t3,&t4,&t5);
                                                 /* select card_0 */
/* step2 : enable all D/I/O port                                  */
outportb(wBase,1);                                /* /RESET -> 1  */

printf("\n\n(2) DEMO4 Interrupt (1Hz) test");

init_int1_low();        /* interrupt initialize, INT1 is low now  */
COUNT_L=0;COUNT_H=0;
printf("\n\n*** Show the count of High_pulse ***\n");

for (;;)
    {
    gotoxy(1,10);
    printf("\nINT count = %d",COUNT_H);
    if (kbhit()!=0) break;
    }

outportb(wBase+5,0);                     /* disable all interrupt */
PIO_DriverClose();
}

/* Use INT_CHAN_1 as internal interrupt signal                    */
void init_int1_low()
{
DWORD dwVal;

disable();

outportb(wBase+5,0);                     /* disable all interrupt */

if (wIrq<8)
   {
   irqmask=inportb(A1_8259+1);
   outportb(A1_8259+1,irqmask & (0xff ^ (1 << wIrq)));
   setvect(wIrq+8, irq_service);
   }
else
   {
   irqmask=inportb(A1_8259+1);
   outportb(A1_8259+1,irqmask & 0xfb);                    /* IRQ2 */
   irqmask=inportb(A2_8259+1);
   outportb(A2_8259+1,irqmask & (0xff ^ (1 << (wIrq-8))));
   setvect(wIrq-8+0x70, irq_service);
   }

/* CLK source = 4 MHz */
pio_da16_c1(0x76,0x90,0x01);       /* COUNTER1, mode3, div    400 */
pio_da16_c2(0xb6,0x10,0x27);       /* COUNTER2, mode3, div  10000 */
                                   /* program Cout2 1Hz squr      */

/* note : the 8254 need extra 2-clock for initialization          */
for (;;)
    {
    if ((inportb(wBase+7)&2)==0) break;      /* wait Cout2 = low  */
    }

/* note : Cout2 = low, INV1 must select the non-inverted Cout2    */
/*        --> INT_CHAN_1 = Cout2 = init_low, active_high          */
outportb(wBase+0x2a,2);            /* INV1 = 1, non-inverted Cout2*/

now_int_state=0;                   /* now Cout2 is low            */
outportb(wBase+5,2);               /* EN1 = 1, enable INT_CHAN_1  */
                                   /* as interrupt source         */
enable();
}

/* -------------------------------------------------------------- */
void interrupt irq_service()
{
if (now_int_state==1)          /* now INT1(Cout2) changed to low  */
   {                           /* --> INT_CHAN_1=!INT1=high now   */
   COUNT_L++;                  /* find a low pulse (INT1)         */
   if((inportb(wBase+7)&2)==0) /* INT1 is still fixed in low  ->  */
     {                         /* need to generate a high pulse   */
     outportb(wBase+0x2a,2);   /* INV1 select non-inverted input  */
                               /* INT_CHAN_1=INT1=low -->         */
                               /* INT_CHAN_1 generate high pulse  */
     now_int_state=0;          /* now INT1=low                    */
     }
   else now_int_state=1;       /* now INT1=high                   */
                               /* don't have to gen. high pulse   */
   }
else                           /* now INT1(Cout2) changed to high */
   {                           /* --> INT_CHAN_1=INT1=high now    */
   COUNT_H++;                  /* find a low pulse (INT1)         */
   if((inportb(wBase+7)&2)==2) /* INT1 is still fixed in high ->  */
     {                         /* need to generate a high pulse   */
     outportb(wBase+0x2a,0);   /* INV1 select inverted input      */
                               /* INT_CHAN_1=!INT1=low -->        */
                               /* INT_CHAN_1 generate high_pulse  */
     now_int_state=1;          /* now INT1=high                   */
     }
   else now_int_state=0;       /* now INT1=low                    */
                               /* don't have to gen. high pulse   */
   }

if (wIrq>=8) outportb(A2_8259,0x20);
outportb(A1_8259,0x20);
}

/* -------------------------------------------------------------- */
void pio_da16_c0(char cConfig, char cLow, char cHigh) /* COUNTER0 */
{
outportb(wBase+0xcc,cConfig);
outportb(wBase+0xc0,cLow);
outportb(wBase+0xc0,cHigh);
}

void pio_da16_c1(char cConfig, char cLow, char cHigh) /* COUNTER1 */
{
outportb(wBase+0xcc,cConfig);
outportb(wBase+0xc4,cLow);
outportb(wBase+0xc4,cHigh);
}

void pio_da16_c2(char cConfig, char cLow, char cHigh) /* COUNTER2 */
{
outportb(wBase+0xcc,cConfig);
outportb(wBase+0xc8,cLow);
outportb(wBase+0xc8,cHigh);
}