CORRIGO E VENTILATION VARIABLES FOR EXOLINE AND MODBUS 3.6 MANU

8 Chapter 1 Corrigo with EXOline, Modbus and BACnet communication
BACnet in E tool
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Addressing
The below picture illustrates the appearance of BACnet addressing in E tool©:
BACnet/IP = Activation status of BACnet/IP protocol.
BACnet device name = The name of the device.
The device ID is devided into two parts, one low and one high. For example: If the high part of the
ID would be “1”, then the device ID above would be “00012640”.
BACnet device ID low = The lower part of the device identification.
BACnet device ID high (x10000) = The higher part of the device identification.
The port number is devided into two parts, one low and one high. For example: In the picture above,
the port number is “47808”.
BACnet/IP UDP port number low = Port number, lower part.
BACnet/IP UDP port number high (x10000) = Port number, higher part. This is the dedicated
communication port.
BBMD address = BACnet Broadcast Management Device address. This is used for communication
over the Internet between devices running BACnet.
Modbus
Communication limitations
The Modbus master must wait for a minimum of 3.5 character times (4 ms at 9600 bps) between two
messages.
Scale factor Modbus
Real signals have scale factor 10, except for the time setting signals which have scale factor 100, and
the air flow signals which have scale factor 1 for Modbus communication. Integer, Index and Logic
always have scale factor 1.
Modbus wiring, etc.
A protocol like Modbus consists of several layers (OSI-model). The bottom layer is always the
physical layer; the number of wires and signal levels. The next layer describes the communication
digits (number of data bits, stop-bits, parity etc). Next are the layers describing the Modbus-specific
functions (number of digits per message, the meaning of different messages, etc.).
For Modbus, the bottom layer can be RS485, RS422, RS232 or Modbus TCP.
Max. 47 registers
A maximum of 47 registers can be read in one message.