Technical data

Communication SFCs for Non-Configured S7 Connections
System Software for S7-300/400 System and Standard Functions - Volume 2/2
22-12 A5E00739858-01
22.5 Writing Data to a Communication Partner outside the
Local S7 Station with SFC 68 "X_PUT"
Description
With SFC 68 "X_PUT," you write data to a communication partner that is not in the
same local S7 station. There is no corresponding SFC on the communication
partner.
The write job is activated after calling the SFC with REQ=1. Following this, you
continue to call the SFC until the acknowledgment is received with BUSY=0.
Make sure that the send area defined with the SD parameter (on the sending CPU)
is the same length as the receive area defined by the VAR_ADDR parameter (on
the communication partner). The data types of SD and VAR_ADDR must also
match.
Parameter Declaration Data Type Memory Area Description
REQ INPUT BOOL I, Q, M, D, L,
constant
Control parameter "request to activate,"
s. Common Parameters of the
Communication SFCs
CONT INPUT BOOL I, Q, M, D, L,
constant
Control parameter "continue," see
Control parameters "request to activate", s.
Common Parameters of the Communication
SFCs
DEST_ID INPUT WORD I, Q, M, D, L,
constant
Address parameter "destination ID." This
contains the MPI address of the
communication partner. You configured
this with STEP 7.
VAR_ADDR INPUT ANY I, Q, M, D Reference to the area on the partner CPU
to which the data will be written. You must
choose a data type that is supported by the
communication partner.
SD INPUT ANY I, Q, M, D Reference to the area in the local CPU that
contains the data to be sent. The following
data types are allowed: BOOL, BYTE,
CHAR, WORD, INT, DWORD, DINT, REAL,
DATE, TOD, TIME,S5_TIME,
DATE_AND_TIME
and arrays of these types except for
BOOL.
SD must have the same length as the
VAR_ADDR parameter at the
communication partner. The data types of
SD and VAR_ADDR must also match.
The maximum length of the send area is 76
bytes
RET_VAL OUTPUT INT I, Q, M, D, L If an error occurs while the function is
being executed, the return value contains
the corresponding error code.
BUSY OUTPUT BOOL I, Q, M, D, L BUSY=1: Sending is not yet completed.
BUSY=0: Sending is completed or no send
function active.