58 • Programmable Field Bus Controller 750-833
Operating
System
WAGO-I/O-SYSTEM
750
Bus System
3.3 Operating System
3.3.1 Run-Up
The controller runs-up after switching on the supply voltage or after a
hardware reset. The PFC user program in the flash memory is transferred to
the RAM . The I/O-LED flashes orange.
The controller then checks the internal bus and the field bus interface .
Following this the I/O modules and the present 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 is shown on the field bus RAM of
the protocol chip. This is followed by the initialization of the system. The
variables are set to 0 or to FALSE or to an initialization 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 "field bus
start" mode . The I/O-LED lights up green.
A PFC user program does not yet exist in the flash memory when delivered.
The controller runs-up as described, without initializing the system. It then
behaves as a coupler.