Wago 750-333 PROFIBUS DP/V1 FIELD BUSCOUPLER 12 MBaud 750-333 Datenbogen
Produktcode
750-333
Fieldbus coupler / controller
• 83
Fieldbus Controller 750-833
WAGO-I/O-SYSTEM 750
D R A F T
PROFIBUS
2001-02-27
3.2.3 Operating
system
3.2.3.1 Run-up
The controller runs-up after switching on the supply voltage or after a hard-
ware reset. The PLC program in the flash memory is transferred to the RAM.
The "I/O" LED flashes orange.
ware reset. The PLC program in the flash memory is transferred to the RAM.
The "I/O" LED flashes orange.
The controller then checks all functions of its modules in a self test, the inter-
nal bus and the fieldbus interface. Following this the I/O modules and the pre-
sent configuration is determined. At the same time a list is generated which is
not visible from outside. This includes an input and an output area, which
shows on the fieldbus RAM of the fieldbus RAM. This is followed by the ini-
tialisation of the system. The variables are set to 0 or to FALSE or to an ini-
tialisation value given by the PLC program. The flags retain their status . The
"I/O" LED blinks red during this phase.
nal bus and the fieldbus interface. Following this the I/O modules and the pre-
sent configuration is determined. At the same time a list is generated which is
not visible from outside. This includes an input and an output area, which
shows on the fieldbus RAM of the fieldbus RAM. This is followed by the ini-
tialisation of the system. The variables are set to 0 or to FALSE or to an ini-
tialisation value given by the PLC program. The flags retain their status . The
"I/O" LED blinks red during this phase.
Following a fault free run-up the controller changes over to the "Fieldbus start"
mode. The "I/O" LED lights up green.
mode. The "I/O" LED lights up green.
A PLC program does not yet exist in the flash memory when delivered. The
controller runs-up as described, without initialising the system. It then behaves
as a coupler.
controller runs-up as described, without initialising the system. It then behaves
as a coupler.
3.2.3.2 PLC
cycle
The PLC cycle starts following a fault free run-up when the operating mode
switch is in the top position or by a start command from the WAGO-I/O-PRO
32. The input and output data of the fieldbus and the I/O modules as well as
the times are read. Subsequently the PLC program in the RAM is processed
followed by the output data of the fieldbus and the I/O modules in the process
image. Operating system functions, amongst others, for diagnosis and commu-
nication are performed an the times actualised at the end of the PLC cycle. The
cycle starts again with the reading in of the input and output data and the
times.
switch is in the top position or by a start command from the WAGO-I/O-PRO
32. The input and output data of the fieldbus and the I/O modules as well as
the times are read. Subsequently the PLC program in the RAM is processed
followed by the output data of the fieldbus and the I/O modules in the process
image. Operating system functions, amongst others, for diagnosis and commu-
nication are performed an the times actualised at the end of the PLC cycle. The
cycle starts again with the reading in of the input and output data and the
times.
The change of the operating mode (STOP/RUN) is made at the end of a PLC
cycle.
cycle.
The cycle time is the time from the start of the PLC program to the next start.
If a loop is programmed within a PLC program the PLC running time and thus
the PLC cycle are extended correspondingly.
If a loop is programmed within a PLC program the PLC running time and thus
the PLC cycle are extended correspondingly.
The inputs, outputs and times are not updated during the processing of the
PLC program. This actualisation occurs in a defined manner only at the end of
the PLC program. For this reason it is not possible to wait for an event from
the process or the elapse of a time within a loop.
PLC program. This actualisation occurs in a defined manner only at the end of
the PLC program. For this reason it is not possible to wait for an event from
the process or the elapse of a time within a loop.