Points Definition - HMS Networks Intesis IN701-KNX Series User Manual

IN701-KNX Series
The Modbus TCP protocol defines different function code types to read/write different register types from the
Modbus devices. It also defines different data formats to encode values.
Also, the data encoding used for 16 bits registers (big-endian or little-endian) can be configured in the Intesis
gateway. This is the byte order for data encoding (MSB..LSB or LSB..MSB)
the Modbus protocol specification, this data encoding varies depending on the manufacturer/type of server.

11.10. Points Definition

Every point defined in the Intesis gateway has the following Modbus features associated with it:
Feature Description
Modbus device Modbus TCP device to which belongs the point, from a list of Modbus TCP server devices that can
be defined in the Intesis gateway (up to 5).
For every defined Modbus TCP server device, a virtual signal is automatically created in the Intesis
gateway to report the communication with the device. Like the rest of the points, this signal is
also available from the field device interface.
Function code 01 Read Coils
Read func. 02 Read Discrete Inputs
Write func. 03 Read Holding Registers
04 Read Input Registers
05 Write Single Coil
15 Write Single Register
06 Write Multiple Coils
16 Write Multiple Register
#Bits Number of bits to be used by this signal.
Data coding • 16/32/48/64 bits unsigned
format
• 16/32/48/64 bits signed (one's complement – C1)
• 16/32/48/64 bits signed (two's complement – C2)
• 16/32/48/64 bits Float
• 16/32/48/64 bits Bitfields
• Error comm
Byte order • Big-endian
• Little-endian
• Word inverted big-endian
• Word inverted little-endian
Register The Modbus register address inside the server device for the point.
address
Bit inside the Bit inside the Modbus register (optional). The Intesis gateway allows bit decoding from generic 16
register bits input/holding Modbus registers.
NOTICE
Some devices use the bit coding into 16 bit input/holding Modbus register to
encode digital values. These registers are generally accessible using Modbus
function codes 03 and 04 (read holding/input registers).
2
MSB: most significant bit; LSB: less significant bit
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2
. Although specified as big-endian in
USER MANUAL Version 1.0
Points Definition