Rockwell Automation 1771-DB Basic Module User Manual - Series A - Manual (Page 141)

Programming
Chapter 6
6–9
Figure 6.7
Sample PLC-5 Family Ladder Logic
Rungs 1 and 2 – Rungs 1 and 2 execute the BTR and BTW instructions
alternately. When the BTR completes the BTW enables immediately
following the BTR scan.
Important: Do not select the continuous mode when using bidirectional
block-transfer. Continuous mode does not allow use of the status bits in the
block-transfer instructions.
Important: Set the block-transfer-write timeout bit (control block, word
0, bit 08) to minimize the impact of the block-transfer instructions on the
program scan time. See the following Section 6.6, “Block-Transfer
Programming Tips” for more information.
6.5
PLC-5 Family Processors
(continued)
6.5.1
Rung Description for
Sample PLC-5 Family
Ladder Logic