Siemens SIMATIC S7-1200

Extended instructions
9.3 Distributed I/O (PROFINET, PROFIBUS, or AS-i)
S7-1200 Programmable controller
394 System Manual, V4.2, 09/2016, A5E02486680-AK
9.3.7
RALRM (Receive interrupt)
You can use the RALRM (Read alarm) instruction with PROFINET and PROFIBUS.
Table 9- 81 RALRM instruction
LAD / FBD
SCL
Description
"RALRM_DB"(
mode:=_int_in_,
f_ID:=_word_in_,
mlen:=_uint_in_,
new=>_bool_out_,
status=>_dword_out_,
ID=>_word_out_,
len=>_uint_out_,
tinfo:=_variant_inout_,
ainfo:=_variant_inout_);
Use the RALRM (read alarm) instruction to read diagnostic
interrupt information from PROFIBUS or PROFINET I/O mod-
ules/devices.
The information in the output parameters contains the start
information of the called OB as well as information of the inter-
rupt source.
Call RALRM in an interrupt OB to return information regarding
the event(s) that caused the interrupt. In the S7-1200. The fol-
lowing Diagnostic OB interrupts are supported: Status, Update,
Profile, Diagnostic error interrupt, Pull or plug of modules, Rack
or station failure.
1
STEP 7 automatically creates the DB when you insert the instruction.
2
In the SCL example, "RALRM_DB" is the name of the instance DB.
Table 9- 82 Data types for the parameters
Parameter and type
Data type
Description
MODE
IN
Byte, USInt, SInt, Int
Operating mode
F_ID IN HW_IO (Word) Logical start address of the component (module) from which interrupts
are to be received
Note
: The device ID can be determined in one of two ways:
• By making the following "Network view" selections:
– Device (gray box)
– "Properties" of the device
– "Hardware identifier"
Note
: Not all devices display their Hardware identifiers.
• By making the following "Project tree" menu selections:
– PLC tags
– Default tag table
– System constants tab
– All configured device Hardware identifiers are displayed.
MLEN IN Byte, USInt, UInt Maximum length in bytes of the data interrupt information to be re-
ceived. MLEN of 0 will allow receipt of as much data interrupt infor-
mation as is available in the AINFO Target Area.
NEW
OUT
Bool
A new interrupt was received.
STATUS OUT DWord Status of the RALRM instruction. Refer to "STATUS parameter for
RDREC, WRREC, and RALRM" (Page 403) for more information.