119
Auxiliary Area (A)
Section 4-7
Precautions
When a Holding Area bit is used in a KEEP(011) instruction, never use a nor-
mally closed condition for the reset input if the input device uses an AC power
supply. When the power supply goes OFF or is temporarily interrupted, the
input will go OFF before the PLC’s internal power supply and the Holding
Area bit will be reset.
Instead, use a configuration like the one shown below.
There are no restrictions in the order of using bit address or in the number of
N.C. or N.O. conditions that can be programmed.
4-7
Auxiliary Area (A)
The Auxiliary Area contains 960 words with addresses ranging from A0 to
A959). These words are preassigned as flags and control bits to monitor and
control operation.
A0 through A447 are read-only, but A448 through A959 can be read or written
from the program or the CX-Programmer.
Refer to Appendix C Auxiliary Area Allocations by Function and Appendix D
Auxiliary Area Allocations by Address for Auxiliary Area functions.
Forcing Bit Status
Read/write bits in the Auxiliary Area cannot be force-set and force-reset con-
tinuously.
Input
Unit
Set input
Reset input
H1.00
Input
Unit
Set input
Reset input
H1.00
Summary of Contents for CP1L-EL20DR-D
Page 3: ...CP1L EL20D CP1L EM30D CP1L EM40D CP1L EL EM CPU Unit Operation Manual Produced July 2017...
Page 4: ...iv...
Page 10: ...x...
Page 22: ...xxii...
Page 34: ...xxxiv Software Licenses and Copyrights 7...
Page 192: ...158 Trial Operation and Debugging Section 5 3...
Page 250: ...216 Automatic Clock Adjustment and Specifying Servers by Host Name Section 6 7...
Page 666: ...632 Trouble Shooting Section 11 7...
Page 696: ...662 Standard Models Appendix A...
Page 805: ...771 Connections to Serial Communications Option Boards Appendix F Connecting to Unit...
Page 806: ...772 Connections to Serial Communications Option Boards Appendix F...
Page 836: ...802 PLC Setup Appendix G...
Page 838: ...804 TCP Status Transitions Appendix H...
Page 840: ...806 Ethernet Network Parameters Appendix I...
Page 842: ...808 Buffer Configuration CP1L EL EM Appendix J...
Page 844: ...810 Ethernet Specifications Appendix K...
Page 851: ...Index 817 work words 118 write protection 447...
Page 852: ...818 Index...
Page 854: ...820 Revision History...
Page 855: ......