KROHNE MFC 010 C Converter - Manual (Page 32)

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MFC010 Interface Manual
6.8 08 (08
16
): Diagnostics
This command function permits the user to per form one of s everal di agnostic oper ations, s uch as
retrieving t he er ror and ev ent l ogs. F or f urther det ails on t his c ommand function, refer to the Modbus
specification.
6.9 11 (0B
16
): Fetch Comm. Event Counter
This function allows the master device to determine if request telegrams are being properly processed.
The Event count returned is a count of the number of request telegrams which have been received and
processed without errors occurring. By fetching the Event count before and after a series of messages the
master can determine whether the messages were handled normally. When the Master device requests
this command function the MFC010 will respond with a two character (16 bit) status value and a two
character event count. The Master request telegram should be formatted as follows.
Request
Character
Field For Example
1 Slave Address 01
16
Request to Slave ID 1
2 Function 0B
16
“Fetch Comm. Event Counter”
3 CRC Lo 41
16
CRC Checksum
4 CRC Hi E7
16
The MFC010 will respond to such a request with a telegram formatted as follows.
Response
Character
Field For Example
1 Slave Address 01
16
Response from Slave ID 1
2 Function 0B
16
“Fetch Comm. Event Counter”
3 Status Hi FF
16
Instrument Status
4 Status Lo FF
16
5 Count Hi 1E
16
Event Count = 7891
6 Count Lo D3
16
7 CRC Lo EC
16
CRC Checksum
8 CRC Hi 12
16
The status value is either FFFF
16
, in which case the slave is still processing a c ommand, or 0000
16
, in
which case the slave is ready to receive the next command request.