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TCP PORT The TCP port runs as a server and is normally connected to a monitor system. The port however also runs a command processor the same as the Satellite port. Both command ports can run simultaneously as each has its buffers for the data. Decoder Output The output of the decoder is formatted to give an eight digit capcode left filled with zeros and a message. Numeric messages give both the 4bit numeric pattern and the 7bit alpha decode pattern. In addition a time stamp at the start of a transmission is sent which includes the frequency and baud rate. The time stamp is preceded with three % symbols and TX_TIME. The time is derived from the real time on board clock. This is updated from the WBB gateway software and is tied to the server time at MTEL. This time is update via the internet on a weekly basis. The outputs below are typical of the decoder.
Satellite Stream failure If the satellite receiver fails to decode the data stream the gateway will report every minute the lack of data as shown below.
Satellite Stream poor signal If the satellite receiver drops the data stream or parts of it the gateway will attempt to lock onto the byte stream and once a valid CRC is generated it knows the decode is working again. It will then attempt to to find the next message boundary such as idle, sync or the next address and continue. So the decoder can operate even if there is corruption in part of the batch.
Configuring the TCP Port The default IP:PORT is 192.168.0.122:10001 The port normally presents decoded messages in a fixed format such that external programs can use the data stream for monitoring purposes. The default IP:PORT is overridden if the flash configuration file contains valid IP:PORT information. The command !IP? will present this information. The !CIP= and !CPORT= are used to send changes to the IP and PORT configurations in the flash memory. In addition the gateway and mask can also be set. Use !CGATEWAY= and !CMASK= to change these parameters from the default of 192.168.0.1 and 255.255.255.0 If the flash memory is corrupt or not present the default is used. To read the IP settings use the !IP? command. The output is the default settings, then the configuration file is read for the IP and Port settings. Finally the last line is the TCP settings as it was initialised to in listen or server mode. An Hyperterminal example of the !IP? command is shown below.
NO_TX setting To make the TCP socket more robust this timer looks at the TCP transmit buffer. If the data in the transmit buffer fails to be sent then the socket is most likely disconnected or there is a major delay in data processing. In this case it is assumed the socket operation is compromised and after this time in seconds the socket is closed and returned to the server (listener) state and waits for a client to re-establish the TCP connection. This setting has a range of operation from 10 to 300 seconds. Use !CNOTX= command to change the value. NO_CONN setting To make the TCP socket more robust this timer looks at the TCP connection. The TCP socket is assumed to be a 24/7 connection. In this case if the TCP socket is unconnected for this time then it assumes the server socket may be compromised and the socket is closed. It immediately reopens a new service and waits for a TCP connection from the client. This setting has a range of operation from 60 to 1800 seconds. Use !CNOCONN= command to change the value. TCP PORT Command Processor Using HyperTerminal or other terminal service program, set up a TCP session. If the TCP settings are unknown then use the satellite port which is a serial port to query the command processor for the TCP settings above. Activate the command processor by typing in a CR until the command processor returns the command prompt MTEL SAT Gateway > This command processor provides very minimal operation as it is not intended to used very often. There is no back space facility when typing in commands. If a command is typed incorrectly just hit CR and start again. When using this port keystrokes are echoed. The processor provides Help, Clock, IP/Port, Power, and Reset commands. To access the help simply hit ? and CR or h and CR or help CR Port Commands If the help is activated the following menu is displayed. In general the clock command will not be required unless the power off command is used. The clock is regularly updated from the WBB port from MTEL. When in command mode the decoder is disabled for 30 seconds and will automatically start up again. The Power OFF command will physically power down all components of the system. This has about a 15 second cycle. The system powers down within a second of the command then a wait period of about 10 seconds then the power is reapplied after which it takes a couple of seconds for the processor to initialise the program. Note the terminal server will need to re-establish the connection to the TCP server port as the connection would have been destroyed in the power cycle process. The IP and PORT commands are entered in dot format. The Soft Reset command simply disables the internal hardware watchdog circuit. This means the watchdog must time out before the processor resets. The advantage to this is the RAM is kept alive so volatile variables will remain the same unless changed by the program re-initialising. The clock is not destroyed and so the start or uptime timestamp will be set correctly. This is important to do after a power up as the clock is lost in the power cycle. Note the terminal server will need to re-establish the connection to the TCP server port as the connection would have been destroyed in the power cycle process. The PRINT-CLOCK command indicates the start time and the current time. A Hyperterminal screen shot is shown below.
The help command provides the following display.
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