Technical data

Table Of Contents
DPV1 SFBs According to PNO AK 1131
System Software for S7-300/400 System and Standard Functions - Volume 1/2
A5E00709327-01
8-5
8.3 Receiving an Interrupt with SFB 54 "RALRM"
Note
The SFB 52 "RALRM" interface is identical to the FB "RALRM" defined in the
standard "PROFIBUS Guideline PROFIBUS Communication and Proxy Function
Blocks according to IEC 61131-3"
Description
The SFB "RALRM" receives an interrupt with all corresponding information from a
peripheral module (centralized structure) or from a DP slave or PROFINET IO
device component. It supplies this information to its output parameters.
The information in the output parameters contains the start information of the called
OB as well as information of the interrupt source.
Call the SFB 54 only within the interrupt OB started by the CPU operating system
as a result of the peripheral interrupt that is to be examined.
Note
If you call SFB 54 "RALRM" in an OB for which the start event was not triggered by
peripherals, the SFB supplies correspondingly reduced information on its outputs.
Make sure to use different instance DBs when you call SFB 54 "RALRM" in
different OBs. If you want to evaluate data that are the result of an SFB54 call
outside of the associated interrupt OB you should moreover use a separate
instance DB per OB start event.
Call of the SFB 54
You can call the SFB54 "RALRM" in three operating modes (MODE). They are
explained in the table below.
MODE The SFB 54 ...
0 ... shows the component that triggered the interrupt in the output parameter ID and sets the
output parameter NEW to TRUE.
1 ... describes all output parameters, independent on the interrupt triggering component.
2 ... checks whether the component specified in input parameter F_ID has triggered the
interrupt.
If not, NEW = FALSE
If yes, NEW = TRUE, and all other outputs parameters are described