Honeywell UDC2500 ユーザーズマニュアル

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Modbus RTU Function Codes 
180 
UDC2500 Universal Digital Controller Product Manual 
4/07 
9  Modbus RTU Function Codes 
9.1  Overview 
This section describes the function codes needed to upload and download the 
configuration from a host computer into this instrument. 
What's in this section? 
The following topics are covered in this section. 
TOPIC 
See Page 
 
9.2   General Information 
This instrument uses a subset of the standard Modbus RTU function codes to provide 
access to process-related information. Several MODICON function codes are 
implemented. It is appropriate to define instrument-specific "user-defined" function 
codes.  Where differences occur between the two protocols it will be noted. Several 
standard Modbus RTU function codes are supported. 
Configuration ID Tags 
Function codes 20 and 21 use the RS422/485 tag IDs for accessing configuration and 
process-related data. These tags are fully explained in Section 10. 
The tag IDs represent the register addresses used in the Request Message. 
Other Modbus Codes  
For Modbus codes other than for accessing configuration and process-related data for 
this controller, refer to the Modbus RTU Serial Communications User Manual # 51-55-
25-66.