Micromod MOD: 1800P - MOD 30ML Identity Module (Version 2) Algorithms, Tables and Sequential Logic Functions - Manual (Page 95)

Logic Functions - Book 2
SUPERVISORY MESSAGE BLOCK
8-87
8.9.5 Using the Supervisory Message Block
The following examples show some typical uses of a supervisory message block.
EXAMPLE 1 LSP Triggered Write Message
The following example shows a write message transaction. The transaction is triggered by the
result of an expression block (EX1) changing from 0 to 1. When the transaction is triggered,
the supervisory message block pulls in the current data from the result of the second
expression block (EX2). This data is stored in the result field and transmitted using a write
message type to the destination instrument. The operator configures the maximum allowed
response time and the maximum number of times to retry the transaction if it is not successful.
A failed transaction triggers a process alarm (PA1).
R
Operator indication of active status, failure
count, message code indicating success
or type of failure, and result quality.
R
SEND
CODE
FCNT
SM1
Send Command
2
1 ICN to
Message
Destination
ICN
FAIL
A
Fail Count
Max Response Time
Data Input
Operator write access to set the
maximum response time and
maximum number of times to retry
the transaction before failure.
Fail
Max Number of Retries
Active
Result
RQ
Result Quality
Message Code
R
Initiating
Logic
Equation
Result
EX1
2
1
Write to Destination
STAT
Alarm, Src
Alarm Status
PA1
To Other Logic
Equation
Result
EX2
Figure 8-46. Example 1: LSP Triggered Write Message