Technical data
Configuration software for SINAUT ST7
1.6 Configuring networks and network nodes in STEP 7 / NetPro
Software
System Manual, 07/2009, C79000-G8976-C222-07
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Acknowledgment
:
The type of an acknowledgment does not depend on the modem used. It is set
dependent on the quality of the transmission line.
Default: short acknowl.
– short acknowl.:
consists of one byte.
– long acknowl.:
consists of 5 bytes. The long acknowledgment is advisable in applications when
interference produces spurious characters on the transmission line that could be
interpreted by the TIM as a short acknowledgment.
example: Bad wireless link
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WAN protocol
:
The WAN protocol is configured for the specific network.
Default: ST7
– ST7:
The ST7 protocol is used as the WAN protocol. They should be the setting in all purely
ST7 networks of an ST7 installation.
– ST1:
The ST1 protocol is used as the WAN protocol. This is required for communication in
networks with old ST1 installations and in networks in which both ST7 subscribers and
ST1 subscribers are connected.
In a SINAUT dedicated line and dial-up network, either the ST1 or the ST7 protocol can
be used. The selected network protocol applies to all subscribers connected to the
relevant network or subnet.
The following combinations of WAN protocol and mode with the dependent frame format
are permitted:
Table 1- 1 Overview of the permitted WAN protocols with various modes (ST7 only)
Network type Mode WAN protocol Asynchronous
characters
Message
format
Dedicated line /
wireless network
Polling ST7 11 or 10 bits FT1.2 or FT2
Dedicated line /
wireless network
Polling with time slots ST7 11 or 10 bits FT1.2 or FT2
Dedicated line /
wireless network
Multi-master polling
with time slots
ST7 10 bits FT2
Dial-up network Spontaneous ST7 11 or 10 bits FT1.2 or FT2
For more information on SINAUT ST1, refer to release 05/2007 of the manual.
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Retry factor
:
This value decides how often a message that has not been acknowledged positively is
repeated.
Range of values: 0 .. 15
Default value in dedicated lines and in the spontaneous network: 3
Default in dial-up network: 7
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Max. message length
(in bytes):
The maximum message length is based on the longest ST7 message length within a
network. Time values (for example sender retry time) for internal monitoring functions are
derived from this information.