Siemens SIMATIC S7-300 Manual page 86

Programming the FM 354
6.2 FC MODE_WR (FC 2) – Control operating modes and
process write jobs
Task You can use FC MODE_WR to:
To do this, you must call FC MODE_WR once in the OB 1 cycle.
The FC performs the following actions:
1. Reads the checkback signals. The values read by the FC are stored in the
2. Transfers the control signals from the user DB (structure CON-
3. Executes the write job from the user DB (JOB_WR), transfers the
4. Generates the status bits JOB_WR.MODE_BUSY (operating mode busy,
Call options
Description of
The following table describes the parameters of this FC.
parameters
DB_NO
RET_VAL INT
Parameter types: I = input parameter, Q = output parameter
6-6
Control modes
Process write jobs
user DB in the structure CHECKBACK_SIGNALS.
TROL_SIGNALS). Depending on the mode selected (CHECK-
BACK_SIGNALS.MODE) control signals CONTROL_SIG-
NALS.START, CONTROL_SIGNALS.DIR_P and
CONTROL_SIGNALS.DIR_M are cleared when a start is detected (edge
generation of signals for FM).
associated data from the user DB, and displays the write job status.
i.e. started) and JOB_WR.POS_REACHED (position reached).
Call in LAD notation
(ladder diagram)
FC MODE_WR
EN
DB_NO
RET_VAL
Name Data P type
type
WORD Q
A
Call in STL notation
(statement list)
CALL MODE_WR(
ENO
DB_NO
RET_VAL
Meaning
Data block number
Return code of SFC 58 "WR_REC"
FM 354 Servo Drive Positioning Module
:= ,
:= );