User's Manual

Chapter Three Configuration
Man_455U-D Rev 3.01 Page 43
If there is no data transfer within the preconfigured “link check” time, the master will send an
empty data message to check the communications link.
The connection will be broken if a communication failure occurs, or if the local or remote
hosts issues a “disconnect” AT command (although this would be unusual for this mode).
When the master is disconnected, it will continuously try to connect to its auto-connect
address.
Up to six repeater addresses may
be configured as part of the auto-
connect address. That is, up to 6
intermediate modules can act as
repeaters between the master and
slave modules.
Auto-Connect Master
At the master unit, you need to
enter the address of the slave.
Select the “RS232 Path” section..
Up to six repeater addresses may
be entered. Repeater modules
may be configured in either
Acknowledged or
unacknowledged mode, but
they must have the same
system address.
The repeater addresses are entered in order from the master - that is, the leftmost address is the
first repeater after the master.
If you enter a “Link Check Time”, then the master unit will send a “check message” if the
check time has elapsed without any data transmissions. For example, if you enter 10 seconds,
then if there is a 10 second period without a data transmission, then the master module will
transmit a check message. If the slave does not acknowledge, then the master will transmit the
check message up to five times (Configurable via S-30). If there is still no ACK, then the
master will reset the link (DCD reset). A value
of zero disables this function.
You can enter address structures for four slaves
– addresses “Z0” to “Z3”. However the host
must use AT commands to select which slave is
required. Without the use of AT commands, the
master will only attempt to connect to the
address configured in “Z0”.
The Z0 to Z3 addresses can be configured by
selecting the “Modem” tag and then the
“Routing” tab.