10 | Channel setup menu 4
124
D-ISC 100 x xx2
Fig.10.28: D‑ISC100 module, status LEDs on the internal Ethernet connection
No./
colour(s)
LED Status Meaning
1
green
On Link - connection to an Ethernet
device established
2
yellow
Flashing Rx/Tx – flash during Modbus
TCP data transfer
Table10.1: Meaning of the status LEDs
The D‑ISC100 acts as a Modbus TCP server. The "Unit Identi-
fier" in the "MBAP Header" of a Modbus TCP request is not eval-
uated by the D‑ISC100. As a result, the D‑ISC100 will respond
to all correctly received Modbus TCP requests that have been
sent to the set IP address. However, we recommend using the
"Unit Identifier" 0xFF indicated in the Modbus specification.
Further information on the use of the Modbus TCP can be found
in the "DURAG D−ISC100 Module Modbus RTU, Module Mod-
bus TCP" manual and in the Modbus specification "Modbus Mes-
saging on TCP/IP Implementation Guide".
(http://modbus.org/docs/Modbus_Messaging_Implementa-
tion_Guide_V1_0b.pdf)
See also 4.2.9 Basic Modbus information [}47].
10.4.1.8 Modbus RTU
Before this software module can be used, it will need to be:
● Activated[
Activate module]
The activation key will need to be entered to do so (see Sec-
tion 10.4.1.2 [Activate modules] [}116]).
● Enabled [
Enable/disable modules](see Section 10.4.1.3 En-
able/disable modules [}116]).