Siemens SITRANS F Coriolis FCT030, Function Manual, Page: 39 / 198

4.7 Float byte order
The device is able to adjust the byte order of floating-point values.
Table 4-5 Float byte order
Modbus
register
Data type /
Size in
bytes
Parameter Description Default value
[units]
(units register)
Value range /
Setting op‐
tions
Access
level
8296 Unsigned /
2
Float byte order The float byte order used in
Modbus messages.
0: 1-0-3-2
1: 0-1-2-3
2: 2-3-0-1
3: 3-2-1-0
The first mentioned byte is
the first byte sent.
Byte 3 corresponds to the
left-most byte (MSB) of a 32
bit floating point number in
big endian format, byte 0 to
the right-most byte
3-2-1-0 0 - 3 Read /
write
4.8 Modbus function codes
Table 4-6 General Modbus settings
Function code Command text Description
01 Read Coils Reads the status of single bit(s)
02 Read Discrete Inputs Reads the status of single input bit(s)
03 Read Holding Registers Reads the binary content of multiple 16-bit registers
04 Read Input Registers Reads the binary content of multiple 16-bit registers
05 Write Single Coil Writes a single on/off bit
06 Write Single Register Writes the binary content of single 16-bit register
07 Read Exception Status Delivers the global alarm status of the device
08 Diagnostics Provides a series of tests for checking the communication sys‐
tem
15 Write Multiple Coils Writes multiple on/off bits
16 Write Multiple Registers Writes the binary content of multiple 16-bit registers
17 Report Slave ID The device will respond to a Report Slave ID command (com‐
mand 17) request from the master by giving information about
device type, vendor, and revision level
23 Read/Write Multiple Registers Combined Write Multiple Registers / Read Holding Registers call
Function code 7 (Read exception status)
The device provides the content of the parameter Global alarm status as exceptions.
MODBUS commands
4.8 Modbus function codes
FCT030 Modbus (From firmware 4.0)
Function Manual, 06/2018, A5E39931813-AB
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