Kontron pITX-SP - Manual (Page 23)

KTD-S0003-C Page 19 CPLD Interface
p ITX-SP Software Guide
6.2 Programming Examples
The following examples (DOS programs) show the access to the CPLD features (C compiler: BORLAND C++).
Note: These programs cannot be run on Linux and Windows
® .
6.2.1 Watchdog Example
#include <stdio.h>
#include <dos.h>
#define CPLD_BASE_ADDR 0xA80
#define WDT_INDEX 0xA2
#define WDT_ENABLE 0x40
#define WDT_TRIGGER 0x80
#define WDT_1SEC 0x00
#define WDT_5SEC 0x01
#define WDT_10SEC 0x02
#define WDT_30SEC 0x03
#define WDT_1MIN 0x10
#define WDT_5MIN 0x11
#define WDT_10MIN 0x12
void ActivateWatchdog (void)
{
outp (CPLD_BASE_ADDR, WDT_INDEX);
outp (CPLD_BASE_ADDR+1, WDT_10SEC);
delay (1); // wait one millisecond
outp (CPLD_BASE_ADDR+1, WDT_ENABLE);
}
void TriggerWatchdog (void)
{
outp (CPLD_BASE_ADDR, WDT_INDEX);
outp (CPLD_BASE_ADDR+1, WDT_TRIGGER | WDT_ENABLE);
delay (1); // wait one millisecond
outp (CPLD_BASE_ADDR+1, WDT_ENABLE);
}
void main (void)
{
int
i;
ActivateWatchdog ();
for (i = 0; i < 5; i++) // wait half of expiry time (= 5 seconds)
delay (1000); // wait 1 second
TriggerWatchdog (); // trigger the watchdog - total expiry time now 15 seconds
}