KROHNE MFC 400 Modbus - Manual (Page 13)

MODBUS PROTOCOL
5
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MFC 400
www.krohne.com 05/2013 - 4002525102 - AD Modbus MFC 400 R02 en
5.7 Diagnostics
This command function permits the user to perform one of several diagnostics operations, such
as retrieving the error and event logs. For further details on this command function, refer to the
Modbus Application Protocol Specification V1.1b.
Modbus Function Code "Diagnostics" (0x08)
5.8 Parameters
The functions of the Modbus interface are arranged in groups of thematically coherent
parameters.
Large gaps have been left between these groups of data types in order to permit expansion of the
signal converter interface and compatibility with further high performance signal converters.
Some registers are protected by a custody transfer lock for use when the signal converter is
used in custody transfer applications. These registers are indicated by the
symbol.
The configuration of the signal converter can be changed via Modbus Holding Registers. Writing
data to those registers does not take effect immediately. In order to apply the new configuration
it is necessary to perform "Apply Changes". Parameters that require "Apply Changes" are
indicated by the symbol. Changes that are not applied can be discarded via "Discard Changes"
(details on page 14). For further information refer to
Application sequences on page 28.
Sub function code Name
dec hex
00 00 Return Query Data
01 01 Restart Communication Option
04 04 Force Listen Only Mode
10 0A Clear Counters
11 0B Return Bus Message Count
12 0C Return Bus Communication Error Count
13 0D Return Bus Exception Count
14 0E Return Slave Message Count
15 0F Return Slave No Response Count
18 12 Return Bus Character Overrun Count