Motorola V186 - Cell Phone - GSM System Planner Manual page 114

Certain configuration steps are performed on the radio itself using the CPS and in the
infrastructure using the UCM tool. See the relevant radio documentation for more
information.
There are two types of hardware interface between the RTU and the radio: For a mobile
radio such as the XTL5000, the interface is comprised of a radio data cable over RS232.
Note: A PC needs a tool called Data Link Manager (DLM) in order to communicate over
the air
NOTE:
ASTRO IV&D does not support group calls (RTU-to-RTU broadcasts). To send a frame
to a group of sites, the application should send to each site individually, leaving a short
wait time between each transmission (300-1000 milliseconds depending upon the
communication used.)
Sending frames from one RTU to another when both are connected to radios may not be
reliable, because of the ASTRO IV&D's limited resources. It is recommended to have an
RTU connected to LAN (CEN) that will route the information between them.
MDLC over iDEN
ACE3600 RTUs can be connected to iDEN iM1000/iM1500 modems (OEM version
≥35.01.00) to communicate using RS232/PPP port on iDEN infrastructure to the IP
network. Since iDEN infrastructure connects to Local Area Networks (LAN) as well, a
LAN-connected
IP Gateway or FEP can communicate directly with these RTUs over iDEN infrastructure.
The iM1000/iM1500 is configured to operate works in various modes, including:
• Packet Data (PD)
• Circuit Data (CD)
• Packet Data over Circuit Data (PD over CD)
MDLC over iDEN, which uses IP technology, deals only with the first mode (PD). The
other two modes can only be used with an external dialup port in the RTU, and do not
support direct communication with another RTU/IP Gateway having an MDLC over IP
port. Therefore they are not relevant to MDLC over IP topic.
In the figure below, the SCADA central and IP Gateway are connected via LAN to iDEN
infrastructure. Each RTU has an iM1000 or iM1500 modem connected to RS232/PPP
Port.
A unique IP address is assigned to each RTU according to its modem's identifier. All
communication between RTUs and the IP Gateway involves sending datagrams in
packets over the network (IP). A PC running ACE3600 STS can be connected directly to
an RTU or operate remotely over IP.
110
Communications