19
KB2: 6-pin Keyboard/Mouse Connector
PIN
Description
1
Keyboard Clock
2
Keyboard Data
3
Mouse Data
4
GND
5
+5V
6
Mouse Clock
1
6
3.16 System Front Panel Control
The HS-7250/HS-7650 series has one LED at location
CN3
that
indicates the system front panel status. This visual feature of the HDD
LED may also be connected to and external HDD LED via connector
CN8
. At location
CN1
is reset button.
CN1: Reset Button Connector
PIN
Description
1
GND
2
Reset
2
1
CN3: HDD LED Connector
PIN
Description
1
Pull 150
Ω
to +5V
2
HDD LED
2
1
CN4: Power LED Connector
PIN
Description
1
Pull 330
Ω
to +5V
2
GND
2
1
3.17 Watchdog Timer
Once the Enable cycle is active a Refresh cycle is requested before the
time-out period. This restarts counting of the WDT period. When the
time counting goes over the period preset of WDT, it will assume that
the program operation is abnormal. A system reset signal will restart
when such error happens.
The following sample programs show how to enable, disable and
refresh the watchdog timer:
