5watchdog, digital i/o and backlight, 1 watchdog example, Jrex plus lx software guide – Kontron JRexplus-LX User Manual
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KTD-S0004-A
Page 13
Watchdog, Digital I/O and Backlight
JRexplus LX Software Guide
5
Watchdog, Digital I/O and Backlight
The following examples (DOS programs) show the access to these three system components (C compiler:
BORLAND C++).
Note: These examples can't be run on Linux and Windows
®
.
5.1
Watchdog Example
#include
#define JIDA16_INT
0x15
#define WDT_INIT
0xE000
#define WDT_TRIGGER
0xE001
#define WDT_TIMEOUT
50 // timeout = 10 seconds (time base = 0.2 seconds)
#define WDT_DELAY
0
// no delay
void ActivateWatchdog (void)
{
union REGS regs;
regs.x.ax = WDT_INIT;
regs.x.bx = WDT_TIMEOUT;
regs.x.cx
=
WDT_DELAY;
regs.x.dx = 0;
// only RESET possible
int86 (JIDA16_INT, ®s, ®s);
}
void TriggerWatchdog (void)
{
union REGS regs;
regs.x.ax = WDT_TRIGGER;
int86 (JIDA16_INT, ®s, ®s);
}
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
}