User manual

Chapter 4 Configuration
MAN_905G_1.16 Page 118
The Fieldbus IN and OUT areas can be configured to a maximum size of 1024 words (2048
bytes) each, depending on the configured fieldbus mappings. The highest mapped location
will correspond to the highest available Modbus register (or coil) available to a Modbus/TCP
client. A Modbus/TCP client must use the appropriate Modbus Coil or Modbus Word
addresses corresponding to configuration software, as well as the correct function code (see
4.10.2 Supported Commands).
Appropriate Modbus prefixes may need to be added to the Modbus Address depending on the
host device. For example, a “word write” fieldbus mapping in the 905G to Modbus location
10, can be read by a host device as 30010 (30000 for an input register + 10 as the address).