Modbus Read, Write and Override Parameters plus Exception Codes 
10 Modbus Read, Write and Override Parameters plus 
Exception Codes 
10.1   Overview 
Introduction 
This section contains information concerning Reading, Writing, and Overriding 
parameters in the UDC3200 Process Controller. There are two types of parameters: 
•  Data Transfer—These parameters include reading control data, option status, and 
reading or changing setpoints. 
•  Configuration Data—All the configuration data is listed in the order in which it 
appears in the controller. 
Each type of parameter has the identifying codes listed with it. 
What's in this section? 
The following topics are covered in this section. 
TOPIC 
10.1 Overview 
10.4  Miscellaneous Read Onlys 
10.5 Setpoints  189 
10.6  Using a Computer Setpoint (Overriding Controller Setpoint) 
10.7 Configuration Parameters  191 
10.8   
See Page 
185 
10.2  Reading Control Data  186 
10.3  Read Options Status  187 
188 
190 
Modbus RTU Exception Codes 219 
 
General Information 
Non-volatile Memory Retention 
•  This controller uses non-volatile memory to store configuration data.  These 
memories are guaranteed to retain data for a minimum of ten years as long as the data 
is not written and erased more than 10,000 times.  In order not to exceed this number, 
it is strongly recommended that configurations which change rapidly such as 
Computer Setpoint use the Override feature which does not affect non-volatile 
memory. 
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