Microsensor MFE600E Operation Manual page 23

0F
10
11
12
14
16
18
1A
1C
1E
22
24
For a multi-byte number transmission, use the BIG-ENDIAN format, that is, use the format with
high-weight bytes first and low-weight bytes after transmission. For example, a four-byte number
ABCDEF12H, the transfer order is: D0= ABH, D1=CDH, D2=EFH, D3=12H. Above D0, D1, D2, and D3
respectively correspond to D0, D1, D2, and D3 in the transmission data sequence described later.
For a two-byte number such as 12ABH, then D0=12H, D1=ABH.
For floating-point numbers, the format is IEEE 754 single-precision, and the transmission order is the
high byte first and then the low byte. The high byte is the byte where the sign bit and exponent bit in the
floating-point number are located, and the low byte is the byte where the mantissa is located.
According to the MODBUS protocol specification, the maximum number of data bytes allowed to be
transmitted in one communication is 250 (125 × 2).
For example:
a) Definition of instantaneous flow information（FLOAT）
Host sends: 01 03 00 00 00 02 C4 0B
Slave response: 01 03 04 D0 D1 D2 D3 CRCL CRCH
b) Definition of unit instantaneous flow information （SHORT/ List type）
Host sends: 01 03 00 02 00 01 25 CA
Slave response: 01 03 02 00 D0 CRCL CRCH
D0 Definition:
D0
unit m
D0
unit ig/m
D0
unit g/s
c) Positive total integer low 4 bit
Host sends: 01 03 00 03 00 02 34 0B
Slave response: 01 03 04 D0 D1 D2 D3 CRCL CRCH
Empty pipe alarm
Upper limit alarm
Lower limit alarm
Flow rate information
Flow percentage
Electrode resistance
Instrument diameter
Positive total integer high
Reverse total integer high
Two-way total cumulative algebra and
Two-way total cumulative algebra and
decimal numbers
Two-way cumulative algebra
and symbols
0 1 2
3 /s m 3 /min m 3 /h
8 9 10
ig/h t/s
16 17
ig/s
message
integers
3 4
L/s L/min
11 12
t/min t/h
definition （LONG）
21
SHORT 2
SHORT 2
SHORT 2
FLOAT 4
FLOAT 4
FLOAT 4
FLOAT 4
LONG 4
LONG 4
LONG LONG 8
FLOAT 4
INT 2
5 6
L/h g/m
13 14
kg/s kg/min
7
g/h
15
kg/h