Pitx-sp software guide – Kontron pITX-SP User Manual

Page 32

KTD-S0003-C

Page 28

CPLD Interface

ITX-SP Software Guide

int flag = 0, reg_val;

void interrupt (*oldISR)(__CPPARGS);

void interrupt gpioISR(__CPPARGS)
{

outp (CPLD_BASE_ADDR, GPIO_OUTPUT);

reg_val |= (IRQ_BIT5 + IRQ_BIT6);

outp (CPLD_BASE_ADDR+1, reg_val);

flag++;

outp (CTRL_8259, EOI);

}

void main (void)
{

int i, count5 = 0, count6 = 0, old_mask, ctrl_val;

clrscr

();

_disable

();

oldISR = _dos_getvect (VECTOR_IRQ7);

_dos_setvect (VECTOR_IRQ7, gpioISR );

old_mask = inp (IMR_8259);

outp (IMR_8259, (old_mask & ~IRQ_MASK));

_enable

();

outp (CPLD_BASE_ADDR, GPIO_IRQ_POLARITY);

outp (CPLD_BASE_ADDR+1, IRQ_FALLING_EDGE);

outp (CPLD_BASE_ADDR, GPIO_OUTPUT);

reg_val = inp (CPLD_BASE_ADDR+1);

reg_val |= (IRQ_BIT5 + IRQ_BIT6);

outp (CPLD_BASE_ADDR+1, reg_val);

outp (CPLD_BASE_ADDR, GPIO_CONTROL);

ctrl_val = inp (CPLD_BASE_ADDR+1);

ctrl_val |= IRQ_ENABLE;

outp (CPLD_BASE_ADDR+1, ctrl_val);

while (! kbhit ())

{

flag = 0;

outp (CPLD_BASE_ADDR, GPIO_OUTPUT);

reg_val &= ~IRQ_BIT5;

outp (CPLD_BASE_ADDR+1, reg_val);

for (i = 0; i < IRQ_TIMEOUT; i++)

if (flag) break;

if (i != IRQ_TIMEOUT)

{

gotoxy (1, 2);

printf ("Interrupt Count GPIO 5 = %d", ++count5);

}

delay

(500);