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Summary of Contents for GBS Serial Watchdog
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Serial Watchdog Documentation and User Manual Version 1.1...
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Exclusion of liability The GBS-Elektronik GmbH is not liable for errors and damages caused by wrong use and improper installation of the Serial Watchdog module. Furthermore the GBS-Elektronik GmbH is not liable for indirect or subsequent damages due to wrong installation and malfunction of the Serial Watchdog.
Table of Contents 0 INTRODUCTION .................. 2 1 INSTALLATION ................... 2 1.1 B 230V AC UPS ..2 UILDING A WATCHDOG MONITORED SYSTEM WITH 1.2 B 24V DC UPS..2 UILDING A WATCHDOG MONITORED SYSTEM WITH 1.3 U ........2 SING THE RESET SWITCH OF THE COMPUTER 2 PRINCIPLE OF OPERATION ..............
1 Installation The Serial Watchdog is usable in different situations. It works with 230V AC computers and with 24V DC systems, too. The two most important installation variants are described in this chapter. The watchdog design allows a maximum of flexibility.
Make sure that it does not exceed the maximum ratings of the relay (see Technical Specifications). Normally the Serial Watchdog is used together with a UPS to buffer power failures. This UPS is not required for proper operation of the watchdog.
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Serial Watchdog Figure 1.1 230V AC system with Serial Watchdog...
The GBS-Elektronik GmbH is not liable for errors and damages caused by wrong use and improper installation of the Serial Watchdog module. Furthermore the GBS-Elektronik GmbH is not liable for indirect or subsequent damages due to wrong installation and malfunction of the Serial Watchdog.
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Serial Watchdog Figure 1.2 24V DC system with Serial Watchdog...
2 Principle of Operation This chapter describes how the Serial Watchdog works. It does not describe the usage and installation of the watchdog program which is necessary to operate the watchdog. For questions concerning this program, please refer to the corresponding user manual / online help.
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Serial Watchdog The number of soft-restarts (initiated by the watchdog program) can be limited by the parameter „Number of Restarts“. Values between 1 and 255 are valid, zero disables the limit. If the counter reaches the limit, it stops restarting the computer and sends now PING-commands with the parameter 0x02 every 30 seconds.
2.2 System behaviour after a power failure If the UPS output supplies the system with power, the computer boots and starts its operating system. Meanwhile the Serial Watchdog runs its initialisation procedure and waits for commands which are sent via the serial port.
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Serial Watchdog After the computer has finished its startup procedure, the watchdog program sends the START-command to the watchdog. Now the watchdog is reactivated. It sets the COMMUNICATION-LED and the STATE-OF-HEALTH-LED flushes red. The watchdog waits 30 seconds for a PING-command. If it receives a ping, it clears all timers and starts waiting again, independent of the parameter.
These code switches can be used to make some time presets changeable by the customer. Furthermore the Serial Watchdog contains a real time clock and an EEPROM. With this combination it would be possible to record some special events like missing pings with time stamps.
4.2 Software Specification Preset Watchdog Time: 30...36000s; changeable in steps of 30s Possible Communication Ports: COM1...COM8 Monitored Event: writing files into a specified (monitored) directory Monitored Directory: free selectable, can be everyone from a local harddisk; all sub-directories are also monitored (optional) Logfile: monitored_dir\watchdog.log...
Serial Watchdog 4.3 Command Set Summary Communication is always initialized by the host computer, the watchdog itself does not start requests. Each time the computer sends a command to the watchdog, it will send an answer back. Commands and answers always consist of 4 bytes. The first byte represents the checksum of the following 3 bytes and the second byte is interpreted as command itself.
Errorcodes Error Byte1 Byte2 Byte3 Byte4 HARDWARE ERROR RCSTA UNKNOWN COMMAND CHECKSUM ERROR CALCC EEDATA ERROR RCSTA corresponds to PIC-Register checksum from firmware calculated 4.4 History Hardware Description 0x10 initial Version Firmware Description 0x10 initial Version 0x11 - Number of restarts changeable - Audiable Alarm changeable - STOH LED is now red flashing after a start command instead of continously green shining...
Herewith we declare that the design of the device described below is in accordance with the mentioned EC regulations. This declaration looses its validity by unauthorized changes. Description: serial controlled watchdog for unattended computer systems Type: Serial Watchdog, Standard Version Year of manufacture: 2001 Applicable EC rules: 73/23/EWG (Niederspannungsrichtlinie) changed by: 93/68/EWG 89/336/EWG (Elektromagnetische Verträglichkeit)
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Do you have a question about the Serial Watchdog and is the answer not in the manual?
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