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Contents
16
20.2 Scan Cycle Control . . . . . . . 272
20.2.1 Process Image Updating. . . . . 272
20.2.2 Scan Cycle Monitoring Time . . 274
20.2.3 Minimum Scan Cycle Time,
Background Scanning . . . . . . 275
20.2.4 Response Time . . . . . . . . . 276
20.2.5 Start Information . . . . . . . . 276
20.3 Program Functions . . . . . . . 278
20.3.1 Time of day . . . . . . . . . . . 278
20.3.2 Read System Clock . . . . . . . 280
20.3.3 Run-Time Meter . . . . . . . . . 280
20.3.4 Compressing CPU Memory . . . 282
20.3.5 Waiting and Stopping . . . . . . 282
20.3.6 Multicomputing . . . . . . . . . 282
20.3.7 Determining the OB Program
Runtime . . . . . . . . . . . . . 283
20.3.8 Changing program protection . . 286
20.4 Communication via Distributed
I/O . . . . . . . . . . . . . . . . 287
20.4.1 Addressing PROFIBUS DP . . . 287
20.4.2 Configuring PROFIBUS DP . . 291
20.4.3 Special Functions for
PROFIBUS DP . . . . . . . . . 300
20.4.4 Addressing PROFINET IO . . . 305
20.4.5 Configuring PROFINET IO . . . 307
20.4.6 Special Functions for
PROFINET IO. . . . . . . . . . 314
20.4.7 System blocks for distributed I/O 323
20.5 Global Data Communication . . 331
20.5.1 Fundamentals . . . . . . . . . . 331
20.5.2 Configuring GD communication 333
20.5.3 System Functions for
GD Communication . . . . . . . 335
20.6 S7 Basic Communication . . . . 335
20.6.1 Station-Internal S7 Basic
Communication . . . . . . . . . 335
20.6.2 System Functions for Station-
Internal S7 Basic Communication 336
20.6.3 Station-External S7 Basic
Communication . . . . . . . . . 338
20.6.4 System Functions for Station-
External S7 Basic Communication 339
20.7 S7 Communication . . . . . . . . 341
20.7.1 Fundamentals . . . . . . . . . . . 341
20.7.2 Two-Way Data Exchange. . . . . 342
20.7.3 One-Way Data Exchange . . . . . 344
20.7.4 Transferring Print Data . . . . . . 345
20.7.5 Control Functions. . . . . . . . . 346
20.7.6 Monitoring Functions. . . . . . .
346
20.8 IE communication . . . . . . . . 350
20.8.1 Basics . . . . . . . . . . . . . . . 350
20.8.2 Establishing and clearing
down connections. . . . . . . . . 351
20.8.3 Data transfer with TCP native
or ISO-on-TCP . . . . . . . . . . 353
20.8.4 Data transfer with UDP. . . . . . 355
20.9 PtP communication with S7-300C 357
20.9.1 Fundamentals . . . . . . . . . . . 357
20.9.2 ASCII driver and 3964(R)
procedure . . . . . . . . . . . . . 358
20.9.3 RK512 computer coupling . . . . 359
20.10 Configuration in RUN . . . . . . 362
20.10.1 Preparation of Changes in
Configuration . . . . . . . . . . 362
20.10.2 Change Configuration . . . . . . 364
20.10.3 Load Configuration . . . . . . . 364
20.10.4 CiR Synchronization Time . . . 365
20.10.5 Effects on Program Execution. . 365
20.10.6 Control CiR Process. . . . . . . 365
21 Interrupt Handling . . . . . . . 367
21.1 General Remarks . . . . . . . . . 367
21.2 Time-of-Day Interrupts . . . . . . 368
21.2.1 Handling Time-of-Day Interrupts 369
21.2.2 Configuring Time-of-Day Interrupts
with STEP 7 . . . . . . . . . . . 370
21.2.3 System Functions for Time-of-Day
Interrupts . . . . . . . . . . . . . 370
21.3 Time-Delay Interrupts . . . . . . 372
21.3.1 Handling Time-Delay Interrupts . 372
21.3.2 Configuring Time-Delay Interrupts
with STEP 7 . . . . . . . . . . . 373
21.3.3 System Functions for Time-Delay
Interrupts . . . . . . . . . . . . . 373