Portwell NANO-5050, User Manual

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System Installation
NANO-5050 User’s Manual 3-3
3.4 Clear CMOS Operation
The following table indicates how to enable/disable Clear CMOS Function hardware
circuit by putting jumpers at proper position.
J14:CMOS Setup (1*3 Pin Header/2.0 mm)
PIN No Description
1-2 Short Normal Operation
Ì
2-3 Short Clear CMOS contents
3.5 WDT Function
The Watchdog Timer of motherboard consists of 8-bit programmable time-out
counter and a control and status register. Reference Winbond Super I/O
W83627DHG-PT Spec chapter 16. The units of Watchdog Timer counter are
selected at Logical Device 8, CR
［
F5h
］
, bit
［
3
］
. The time-out value is set ar
Logical Device 8, CR
［
F6h
］
. Writing zero disables the Watchdog Timer function.
Writing any non-zero value to this register causes the counter to load this value into
the Watchdog Timer counter and start counting down.
WDT Control Command Example
#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include <dos.h>
void change_LDN (unsigned char LDN)
{
outportb(0x2E, 0x07);
outportb(0x2F, LDN);
}
void set_CFG (unsigned char Add, unsigned char Value)
{
outportb (0x2E, Add);
outportb (0x2F, Value);
}
int main(void)
{
unsigned char temp;
// Initialze WDT function
temp = get_CFG (0x2D) & ~0x01;
set_CFG (0x2D, temp);
change_LDN (0x08);