Siemens CPU 313C Hardware And Installation Manual page 229

6FDQ UDWH
The reduction rate determines the send/receive frequency for Æ GD packets on
the basis of the CPU cycle.
6)%
Æ System function block
6)&
Æ System function
6HJPHQW
Æ Bus Segment
6LJQDO PRGXOH
Signal modules (SM) form the interface between the process and the PLC. There
are digital and analog I/O modules (input/output module, digital or analog).
(input/output module, analog)
6ODYH
A slave may only exchange data with the Æ Master on request.
67$5783
A STARTUP routine is executed at the transition from STOP to RUN mode. Can be
triggered by the Æ mode selector switch or after power on, or by an operator action
on the programming device. An S7–300 performs Æ a restart.
67(3 
Programming language for developing user programs for SIMATIC S7 PLCs.
6XEVWLWXWH YDOXH
Substitute values are configurable values which output modules transfer to the
process when the CPU switches to STOP mode.
In the event of an input access error, a substitute value can be written to the
accumulator instead of the input value which could not be read (SFC 44).
S7-300 Automation Systems, Hardware and Installation: CPU 31xC and CPU 31x
A5E00105492-03
*ORVVDU\
13-13