Synchronization Messages; Using At Commands - GE TransNET 900 Reference Manual

All Remotes synchronize to a corresponding Master. This can be the "real
Master" (the
MODE M
synchronization from the "real Master."
Payload polls/packets broadcast from the network Master will be repeated to
all levels of the network, either directly to Remotes, or through network
repeaters—the Extension station. The targeted Remote responds to the poll
following the same path back to the Master.

Synchronization Messages

Remotes acquire synchronization and configuration information via
messages. They can synchronize to the Master (the
valid Extension (a
The Master will always transmit
start sending
SYNC
Master.
The ability to synchronize to a given radio is further qualified by the sender's
Extended Address (
( , , and
XMAP XPRI
When a primary is specified (
find the primary first. If 30 seconds elapses and the primary is not found, then
the radio attempts to synchronize with any non-primary radio in the
list.
Once every 30 minutes, if a primary is defined, the radio will check its
synchronization source. If the radio is synchronized to a unit other than the
primary, then the current
is less than
XRSSI
loss-of-synchronization, and hunt for the primary again (as described in the
previous paragraph).
By default, Extensions (and the Master) begin with
tion qualifiers are set to
default configuration allows any radio to hear the Master. When an Extension
is added, the extended address of the Extension radio must be set to a unique
value. All Remotes that need to hear that extension can specify this either by
designating the extension as the primary (
of valid synchronization sources (

9.3 Using AT Commands

A TransNET network may be configured to support protocols employing
Hayes-Compatible modem commands through the radio's AT Mode. In this
mode, TransNET units can provide a communications replacement for
dial-up modems where the RTUs and the protocol do not contain address-
ability, and the establishment of a direct-communications link is the only way
to determine if the RTU has data ready to be sent. This requirement is
common in many older SCADA systems which were developed for direct
MDS 05-2708A01, Rev. F
unit), or it can be a repeater "Extension" that derives
unit).
MODE X
SYNC
messages after synchronization is achieved with its
) and by the receiver's Synchronization Qualifiers
XADDR
).
XRSSI
is 0...31), a radio will always attempt to
XPRI
value is compared to the
RSSI
(or if is
XRSSI NONE
,
XMAP 0 XPRI 0
XMAP
MDS TransNET Ref. Manual
MODE M
messages. An Extension will only
XRSSI
) the radio will force a
XADDR
, and
XRSSI NONE
), or by including it in their list
XPRI
).
SYNC
unit) or to any
XMAP
value. If
RSSI
. Synchroniza-
0
, respectively. This
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