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Download 1775-6.4.1, PLC-3 Family Programmable Controller, Programming
Transcript
Chapter 15 Executing Block Transfers Figure 15.6 Timing Diagram for Block-transfer Operations First program scan after block transfer is completed and rung becomes false Scanner completes block transfer Processor queues block tranfer request First program scan after block transfer is completed Processor scans rung Transitional condition on rung Set Reset Enable (EN) Latch–enable (EN) Request (RQ) Scanner–done or Scanner–error (SD or SE) Done or Error (DN or ER) 15-10 Minimum of one program scan
