YOKOGAWA UT150L, Руководство пользователя

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IM 05C01E22-10E
4-3
Chapter 4 MODBUS Communication
4.2 Communication with Host Device
The specification of D registers for a message using commercially available SCADA or the like and
specification of D registers for a message in customer-created communication programs are different
from simple specification of D register numbers. Thus, care should be taken.
(1) When using commercially available SCADA or the like, specify the D register numbers by
changing them into reference numbers. D register numbers whose “D” leading character is replaced
with “4,” are treated as reference numbers. (When using a DDE server or others, specify these
reference numbers.)
(2) For communication programs created by the customer, specify registers using the hexadecimal
numbers of values that are obtained by subtracting “40001” from the reference numbers. (Thus,
hexadecimal numbers are those to be specified.)
Example: To specify target setpoint “D0120”:
(1) For a message using commercially available SCADA or the like, specify reference number
“40120.”
(2) For a message in a customer-created communication program, specify the hexadecimal number, or
0077, of a value (0119) obtained by subtracting 40001 from the reference number.
4.2.1 List of Function Codes
Function codes are command words used by the higher-level device to obtain the D register informa-
tion of UT150L.
Table 4-2 List of Function Codes
Code Number
03
06
08
16
• A write using the function code is not possible for read-only or disabled D registers.
• Broadcast can be specified for function codes 06 and 16 only.
Function
Writes data into D register.
Performs loop back test.
Reads data from multiple D registers.
Writes data into multiple D registers.
Capable of writing data to one D register between D0101 and
D0421.
Capable of reading data from a maximum of 32 successive D
registers between D0001 and D0421.
Description
See subsection 4.2.3, “Function Codes.
Capable of writing data into a maximum of 32 successive D
registers between D0101 and D0421.