Technical data

Generating Block-Related Messages
System Software for S7-300/400 System and Standard Functions - Volume 2/2
A5E00739858-01
24-13
24.5 Generating Block-Related Messages with Associated
Values for Eight Signals with SFB 35 "ALARM_8P"
Description
SFB 35 "ALARM_8P" represents a linear extension of SFB 33 "ALARM" to eight
signals.
As long as you have not enabled acknowledgement triggered reporting, a message
will always be generated when a signal transition is detected at one or more
signals (exception: a message is always sent at the first block call). All eight signals
have a common message ID that is split eight individual messages on the display
device. You can acknowledge each individual message separately or a group of
messages.
You can use the ACK_STATE output parameter to process the acknowledgment
state of the individual messages in your program. If you disable or enable a
message of an ALARM_8P block, this always affects the entire ALARM_8P block.
Disabling and enabling of individual signals is not possible.
One message memory with 2 memory blocks is available for each instance of
SFB35 "ALARM_8P".
For information on saving signal transitions to intermediate memory refer to the
section "Signal transition detection" in the Introduction to Generating Block-Related
Messages with SFBs.
Parameters Declaration Data Type Memory Area Description
EN_R INPUT BOOL I, Q, M, D, L,
constant
Control parameter enabled to receive
that decides whether the output
ACK_STATE is updated at the block
call (EN_R=1) or not (EN_R=0).
SIG_i, 1 = i = 8 INPUT BOOL I, Q, M, D, L i(th) signal to be monitored
ID INPUT WORD I, Q, M, D, L,
constant
Data channel for messages:
W#16#EEEE ID is only evaluated at
the first call.
EV_ID INPUT DWORD I, Q, M, D, L,
constant
Message number (0 not permitted)
EV_ID is only evaluated at the first call.
Subsequently, the message number
used for the first call applies to every
call of SFB 35 with the corresponding
instance DB.
STEP 7 assigns the message number
automatically to ensure consistency of
the message numbers. The message
numbers within a user program must
be unique.
SEVERITY INPUT WORD I, Q, M, D, L,
constant
Weighting of the event
Possible values: 0 through 127
(value 0
means highest weighting)
This parameter is irrelevant for
processing this message.