Chapter 6 Communication
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Register address description:
Address
Data type
Date size
Function
code
Description
Access
authority
0x0000
Unsigned
long
4 bytes
0x03
pH value (default two
decimal places)
Read only
0x0002
Short
2 bytes
0x03
Temperature (default
1 decimal)
Read only
0x0003
Unsigned
long
4 bytes
0x03
ORP value (signed
integer)
Read only
Communication case
：
The computer sends: 00 03 00 00 00 01 85 DB
pH / ORP Table Returns: 00 03 02 02 AE 05 58
Return command comment:
00 is 485 address;
03 is the function code;
02 is the data length of the return pH value: 2 bytes;
02 for the return of the pH value of 686 (hex high byte);
AE for the return of the pH value of 686 (hex low byte);
05 58 is the CRC check value;
Example of temperature reading:
Computer sends: 00 03 00 02 00 01 24 1B
Conductivity meter returns: 00 03 02 00 FA 05 C7
Return command annotation:
00 is the address of slave, which can be configured in the instrument;
03 is function code, reading and holding register;
02 is the length of data of returned temperature value, 2 bytes;
00 FA is the returned temperature value, 25.0
℃
, unit:
℃
.
The value obtained shall be divided by 10 to get the current temperature value. The
range: -10.0-130.0
℃
.
05 C7 is the CRC16 check code, which is varying depending on different data;
