Siemens SIMATIC S5 Manual page 78

Startup, Loading and Operating States
Table 7-1. Operator Inputs - Loading Via the I/O Bus
Operating State
of the CPU
RUN
STOP via mode
selector switch
STOP caused by
error in the CPU user
program or operator
input on
programmer/PC
STOP due to
hardware error
If the CPU was switched to STOP before beginning the loading procedure, the CPU user program is
unlinked during loading of the IP 265 via the I/O bus. A fault during the loading procedure (e.g.
POWER OFF or connecting cable between programmer and CPU unplugged) may lead to a loss of
the CPU user program. The CPU user program must be reloaded from the memory submodule into
the CPU.
Status information
During automatic loading of the IP 265, the control bit is set in the status word. The control bit
indicates to the CPU user program that the IP 265 is controlled by COM 265. When all data blocks
of the user program have been transmitted to the IP 265, it sets the status bit "IP 265 loaded".
If an error occurs during the loading procedure, the IP 265 enters the STOP state. COM 265 outputs
the relevant error message on the programmer/PC screen. The STOP LED flashes. The error flags
"group error" and "loading error" additionally appear in the control word.
Note
After a successful loading procedure, the IP 265 enters the STOP state. With the aid of
COM 265, the IP 265 can be switched to the RUN state immediately after loading.
Duration of the loading procedure
The IP 265 user program is transmitted within 1000 data cycles. At an average CPU scan time of
20 ms, the loading procedure would last approx. 20 s. If a connected EEPROM memory submodule
is overwritten simultaneously, the entire loading procedure lasts approx. 80 s.
7-6
User Handling
No further user inputs necessary
Mode selector switch of the CPU
must be set to RUN prior to loading.
After the loading procedure, the CPU
must be switched to STOP again.
No other user inputs necessary
Loading only possibly if error has
been eliminated
Effects
CPU user program continues to
work, IP 265 program execution is
interrupted
CPU user program is not
processed
CPU is briefly switched to RUN by
COM 265.
However, CPU user program is
not processed.
EWA 4NEB 812 6130-02a
IP 265