Siemens SITRANS F Series, Operating Instructions Manual, Page: 132 / 362

Modbus communication
A.5 Integer byte order
SITRANS F Ultrasonic flowmeters FST030 (Modbus)
130
Operating Instructions, 08/2017, A5E37367739-AC
A.5 Integer byte order
The device is able to adjust the byte order of integer values.
Table A- 4 Integer byte order
Modbus
register
Data type /
Size in
bytes
Parameter Description Default value
[units]
(units regis-
ter)
Value range /
Setting op-
tions
Access
level
8295 Unsigned /
2
Integer order byte The integer byte order used
in Modbus messages.
0: MSB - LSB (big endian)
1: LSB - MSB (little endian)
MSB = most significant byte
/ high byte
LSB = least significant byte /
low byte
MSB - LSB
(big endian)
0 - 1 Read /
write
A.6 Float byte order
The device is able to adjust the byte order of floating-point values.
Table A- 5 Float byte order
Modbus
register
Data type /
Size in
bytes
Parameter Description Default value
[units]
(units regis-
ter)
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