T24-Bsi And T24-Bsu [Base Station] - Mantracourt T24-BSi Technical Manual

T24-BSi and T24-BSu [Base Station]

Overview
These devices are base stations and interface between the radio and a physical interface for a connection to a
PC, PLC or other device.
Addressing
Usually only a single base station is required in a telemetry installation. If a telemetry device is outside the range
of the base station a repeater may be deployed.
Some complex topologies may only be realized by using multiple base stations which may require changes to the
Address switches. See Multipoint Base Station Section.
Multipoint Base Stations
Sometimes more than one base station is required in a system. This may simply be a central PC with two base
stations wired off in opposite directions.
Where one base station handles devices on the left and the other those on the right.
Multiple base stations allow flexibility in routing requests from a PC as each time a packet is sent to a base
station it is targeted to a particular base station Address. When a packet arrives back at a PC it contains the
Address of the base station that routed it.
If a base station is the only one connected to a particular serial port then every base station can have Address 1
as the PC will send packets to a particular port to select which base station handles a packet, likewise packets
arriving back at the PC will be identified by the port that they arrive on.
RS232 devices can only be connected one at time anyway but RS485 allows multiple devices on the same bus. This
is where the Addressing is vital as it is this that distinguishes between base stations.
When using USB base stations you may only ever have one T24-BSu connected to a PC at any time. Using T24-BSi
will allow multiple USB base stations to be connected to single PC. Unique Addresses are again required in this
instance.
Note that broadcast packets can be received by multiple base stations so packets may appear duplicated at the
PC end.
It is also possible for the PC to route a packet through all connected base stations by Addressing a packet to
Address 0.
NOTE: Although it is possible to connect multiple USB base stations to a PC the T24drv.dll driver supplied by
Mantracourt only supports one Base Station Addressed as 1.
So when using a T24-BSi which supports USB but also has a DIP switch to allow Address setting the Address must
be set to 1. The T24-BSu devices are manufactured with a fixed Address of 1.
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Mantracourt Electronics Limited T24 Technical Manual