Suntex CT-6110-POL, Operation Manual

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9.3 Modbus example description(ex: function code 03H)
The following description takes the temperature reading(0037H) as an example. Set the
temperature at the transmitter at MTC 25.1
o
C, and confirm that host and sub-machine
communication format settings are correct. The host according to the following left table to
send commands, and then to get the response from sub-machine according to following
right table. This example shows the message transmission function code 03H data format. If
under other function code, the logic mode is the same.
ASCII Mode:
Request Response
Message Framing Hex Message Framing Hex
ID, Address 01 ID, Address 01
Function code 03 Function code 03
Starting Address Hi 00 Byte Count 04
Starting Address Lo 37 Register value Hi CC
No. of Registers Hi 00 Register value Lo CD
No. of Registers Lo 02 Register value Hi 41
LRC C3 Register value Lo C8
LRC 56
RTU Mode:
Request Response
Message Framing Hex Message Framing Hex
ID, Address 01 ID, Address 01
Function code 03 Function code 03
Starting Address Hi 00 Byte Count 04
Starting Address Lo 37 Register value Hi CC
No. of Registers Hi 00 Register value Lo CD
No. of Registers Lo 02 Register value Hi 41
CRC Check Lo 75 Register value Lo C8
CRC Check Hi C5 CRC Check Lo 65
CRC Check Hi 5A
Note: FLOAT is a 32-bit IEEE 754 format. The above table, for an example, is divided
into two 16-bit register data transmission. The back 16-bit register(CC CD) will be
transferred first, and then the first 16-bit register (41 C8) will be transferred later.
Every 16-bit format is high-bit in the front and low-bit in the post. For example, the
temperature now is 25.1
o
C. The 16-bit of FLOAT data(Hexadecimal) will show
41 C8 CC CD. The transmission order is CC CD 41 C8.
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