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The WatchDog Timer is a device to ensure that standalone systems can 
always recover from abnormal conditions that cause the system to 
crash. These conditions may result from an external EMI or a software 
bug. When the system stops working, hardware on the board will 
perform hardware reset (cold boot) to bring the system back to a known 
state. 

Three I/O ports control the operation of WatchDog Timer. 

 

443 (hex) 

Write 

Set WatchDog Time period 

443 (hex) 

Read 

Enable the refresh the WatchDog Timer.

043/843 (hex) 

Read 

Disable the WatchDog Timer. 

 

Prior to enable the WatchDog Timer, user has to set the time-out period. 
The resolution of the timer is 1 second and the range of the timer is from 
1 sec to 255 sec. You need to send the time-out value to the I/O port – 
443H, and then enable it by reading data from the same I/O port – 443H. 
This will activate the timer that will eventually time out and reset the CPU 
board. To ensure that this reset condition won’t occur, the WatchDog 
Timer must be periodically refreshed by reading the same I/O port 443H. 
This must be done within the time-out period that is set by the software, 
please refer to the example program. Finally, we have to disable the 
WatchDog timer by reading the I/O port -- 843H or 043H. Otherwise the 
system could reset unconditionally. 

A tolerance of at least 5% must be maintained to avoid unknown 
routines in the operating system (DOS), such as disk I/O that can be 
very time-consuming. Therefore if the time-out period has been set to 10 
seconds, the I/O port 443H must be read within 7 seconds

.

 

 

 

54

Example assembly program: 

TIMER_PORT   =  443H 

TIMER_START  =  443H 

TIMER_STOP   =  843H

 

 

;;INITIAL TIMER COUNTER 

MOV DX, TIMER_PORT 

MOV AL, 8   

 

;;8 seconds

 

OUT DX, AL

    

MOV DX, TIMER_START 

IN AL, DX

.    

;;START COUNTER

 

 

W_LOOP: 

MOV DX, TIMER_STOP 

IN AL, DX 

MOV DX, TIMER_START

 

IN AL, DX

        

;;RESTART COUNTER

 

;;ADD YOUR APPLICATION HERE 

CMP EXIT_AP, 0 

JNE W_LOOP 

MOV DX, TIMER_STOP 

IN AL, DX 

;;EXIT AP 

Summary of Contents for ROCKY-3722EVS

Page 1: ...t contains proprietary information protected by copyright All rights are reserved No part of this manual may be reproduced by any mechanical electronic or other means in any form without prior written...

Page 2: ...Mouse Connector 18 3 6 External Switches and Indicators 19 3 7 USB Port Connector 20 3 8 IrDA Infrared Interface Port 20 3 9 CPU SYSTEM Fan Connector 20 3 10 LAN RJ45 STATE LED Connector 21 3 11 VGA...

Page 3: ...SDRAM RAM This board has a built in DiskOnChip DOC Flash Disk Socket for embedded applications The DOC Flash Disk is 100 software compatible with hard disks Users can use any DOS command without any e...

Page 4: ...Amplitude Shift Keyed IR ASKIR interface USB port Supports two USB ports for future expansion Watch dog timer Can be set by PROGRAM period Reset or NMI is generated when CPU does not periodically tri...

Page 5: ...2 x2 and Printer Cable with bracket One FDD cable One HDD cable One SCSI cable One 6 pin Mini Din convert to two 6 pin mini Din cable for keyboard and mouse connection If any of these items are missin...

Page 6: ...yout of ROCKY 3722EVS is shown and the unpacking information that you should be careful is described The jumpers and switches setting for the ROCKY 3722EVS s configuration such as CPU type selection s...

Page 7: ...tion JP4 JP5 Celeron 1 2 1 2 Pentium III 2 3 2 3 12 JP8 CPU Multiplier Setting Speed 1 2 3 4 5 6 7 8 3 0 x CLOSE OPEN CLOSE CLOSE 3 5 x CLOSE OPEN OPEN CLOSE 4 0 x OPEN CLOSE CLOSE CLOSE 4 5 x OPEN CL...

Page 8: ...IRQ12 for PS 2 Mouse Operating OPEN Disable PS 2 Mouse Release IRQ12 to bus 2 8 SMI Type Setting JP13 JP13 DESCRIPTION 1 2 Single processor 2 3 Dual processors 14 3 Connection This chapter describes...

Page 9: ...E IDE Disk Drive Connector CN4 CN6 You can attach four IDE Integrated Device Electronics hard disk drives on two channels These connectors support Ultra DMA33 IDE devices Non DMA33 devices are sugges...

Page 10: ...2 COM1 3F8 IRQ4 CN10 COM2 2F8 IRQ3 18 Serial Port 10 pin Connector PIN NO DESCRIPTION 1 DATA CARRIER DETECT DCD 2 RECEIVE DATA RXD 3 TRANSMIT DATA TXD 4 DATA TERMINAL READY DTR 5 GROUND GND 6 DATA SET...

Page 11: ...N14 USB0 CN15 USB1 PIN NO DESCRIPTION PIN NO DESCRIPTION 1 VCC 1 VCC 2 DATA 2 DATA 3 DATA 3 DATA 4 GROUND 4 GROUND 3 8 IrDA Infrared Interface Port CN8 The ROCKY 3722EVS has a built in IrDA port which...

Page 12: ...22EVS provides two SCSI connectors Port A 22 and Port B Each port supports 16 SCSI devices at 160Mbps speed There are also two connectors indicating the status of the SCSI channels CN5 Port A CN7 Port...

Page 13: ...ds the system information contained in the CMOS and begins the process of checking out the system and configuring it When it finishes the BIOS will seek an operating system on one of the disks and the...

Page 14: ...lighted item To exit the Help Window press Esc or the F1 key again If after making and saving system changes with Setup you discover that your computer no longer is able to boot the Award BIOS support...

Page 15: ...e minimum requirements for your system to operate Load Setup Defaults The chipset defaults are settings which provide for maximum system performance While Award has designed the custom BIOS to maximiz...

Page 16: ...Note that the specifications of your drive must match with the drive table The hard disk will not work properly if you enter improper information for this category If your hard disk drive type is not...

Page 17: ...e stopped and you will be prompted All But Keyboard The system boot will not stop for a keyboard error it will stop for all other errors All But Diskette The system boot will not stop for a disk error...

Page 18: ...A System will first search for CDROM drive then hard disk drive and the next is floppy disk drive C CDROM A System will first search for hard disk drive then CDROM drive and the next is floppy disk d...

Page 19: ...racters per second 30 30 characters per second Typematic Delay Msec When the typematic rate is enabled this selection allows you to select the delay 36 between when the key was first depressed and whe...

Page 20: ...Enabled Disabled EDO DRAM Speed Selection The DRAM timing is controlled by the DRAM Timing Registers The timings programmed into this register are dependent on the system design Slower rates may be re...

Page 21: ...result Enabled Video BIOS access cached Disabled Video BIOS access not cached 40 Video RAM Cacheable Select Enabled allows caching of the video RAM resulting in better system performance However if an...

Page 22: ...ld seletion the system power AT or ATX 4 9 Power Management Setup The Power Management Setup allows you to configure you system to most effectively save energy while operating in a manner consistent w...

Page 23: ...blanked V H SYNC Blank This selection will cause the system to turn off the vertical and horizontal synchronization ports and write blanks to the video buffer Blank Screen This option only writes bla...

Page 24: ...5 75 0 VGA Active Monitor When Enabled any video activity restarts the global timer for Standby mode The Choice Enabled Disabled Soft Off by PWR BTTN When Enabled turning the system off with the on of...

Page 25: ...ave this field Disabled Select Enabled to reset Extended System Configuration Data ESCD when you exit Setup if you have installed a new add on and the system reconfiguration has caused such a serious...

Page 26: ...If your hard drive and your system software both support Ultra DMA 33 select Auto to enable BIOS support The Choice Auto Disabled On Chip Primary Secondary PCI IDE The integrated peripheral controller...

Page 27: ...length and press Enter The password typed now will clear any previously entered password from CMOS memory You will be asked to confirm the password Type the password again and press Enter You may als...

Page 28: ...imer that will eventually time out and reset the CPU board To ensure that this reset condition won t occur the WatchDog Timer must be periodically refreshed by reading the same I O port 443H This must...

Page 29: ...rt 1 3B0 3DF Standard AGP Graphic Adapter 3F0 3F7 Floppy Disk Controller 3F8 3FF Serial Port 1 443 Watch dog timer enable 843 043 Watch dog timer disable 56 1 st MB Memory Address Map Memory address D...

Page 30: ...18 power button and pin 20 5VSB of CN13 on the board And connect the power cable from backplane to CN13 of CPU card If you want to turn ON the system just press the button once And If you want to tur...

Page 31: ...er supply will be switched on when there is a ring signal detected on pin RI of serial port When your computer is in power down status you can see LAN Link Active LED is flashing This status indicates...

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