Microsensor MFE600H Series, Руководство по эксплуатации

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Data definition: The cumulative amount is a 16-byte hexadecimal fixed point number, and the
instantaneous amount (including flow, velocity, etc.) is a 4-byte IEEE 754 single-precision floating
point number.
Communication command: Function code 03
（
or 04
）
- reading display data
Table 12
Send Receive
01 Address 01 Address
03 Function code 03 Function code
00 Register address high 04 Byte numbers
00 Register address low (display address) 80 Data 1
00 Register numbers high 04 Data 2
02 Register numbers low 80 Data 3
CRCH CRC Check code is high 80 Data 4
CRCL CRC Check code is low CRCH CRC Check code is high
CRCL CRC Check code is low
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
。
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.
Above D0, D1, D2, and D3 respectively correspond to D0, D1, D2, and D3 in the transmission data
sequence described later.
The cumulative value is composed of two parts, the integer part and the fractional part. The integer
part and the fractional part are read out according to the specified address. The fractional part is a
single-precision floating-point number, and the total cumulative value is obtained by adding the
integer part. The integer part is a binary number, set as X, and the fractional part is Z, then there is
the accumulated value SUM:
SUM = X + Z
For example: the integer part data is 1234AB67H (hexadecimal number), the fractional part is 0.567f,
then 1234AB67H = 305,441,639 (decimal) For the cumulative value result SUM, there are:
SUM = 123 0.567f = 305441639.567
Calculation of temperature: The inlet and outlet temperature value data read from the specified
register needs to be divided by 10 to get the actual temperature value, the unit is Celsius, if the read
value is hexadecimal number ABH, the corresponding decimal number is 171, then the actual
temperature value is 17.1 °C