21
Part Names and Functions
Section 2-1
(3)
DIP Switch
CPU Units with 30 or 40 I/O Points
Note
The following data will be write-protected if pin SW1 is turned ON:
• The entire user program (all tasks)
• All data in parameter areas (such as the PLC Setup)
When SW1 is turned ON, the user program and the data in the pa-
rameter areas will not be cleared even if the All Clear operation is
performed from a Peripheral Device (i.e., the CX-Programmer).
CPU Units with 20 I/O Points
No.
Setting
Description
Application
Default
SW1
ON
User memory write-
protected (See note.)
Used to prevent pro-
grams from being inad-
vertently overwritten.
OFF
OFF
User memory not
write-protected.
SW2
ON
Data automatically
transferred from
Memory Cassette at
startup.
Used to enable pro-
grams, Data Memory, or
parameters saved on a
Memory Cassette to be
opened by the CPU Unit
at startup.
OFF
OFF
Data not transferred.
SW3
ON
A395.12 ON
This pin enables control-
ling a bit in memory with-
out using an input relay.
OFF
OFF
A395.12 OFF
SW4
ON
Used for peripheral
bus.
Used to enable a Serial
Communications Option
Board mounted in Option
Board Slot 1 to be used
by the peripheral bus.
OFF
OFF
According to PLC
Setup.
SW5
ON
Used for peripheral
bus.
Used to enable a Serial
Communications Option
Board mounted in Option
Board Slot 2 to be used
by the peripheral bus.
OFF
OFF
According to PLC
Setup.
SW6
OFF
Keep turned OFF.
---
OFF
No.
Setting
Description
Application
Default
SW1
ON
User memory write-
protected (See note.)
Used to prevent pro-
grams from being inad-
vertently overwritten.
OFF
OFF
User memory not
write-protected.
SW2
ON
Data automatically
transferred from
Memory Cassette at
startup.
Used to enable pro-
grams, Data Memory, or
parameters saved on a
Memory Cassette to be
opened by the CPU Unit
at startup.
OFF
OFF
Data not transferred.
SW3
ON
A395.12 ON
This pin enables control-
ling a bit in memory with-
out using an input relay.
OFF
OFF
A395.12 OFF
SW4
ON
Used for peripheral
bus.
Used to enable a Serial
Communications Option
Board mounted in Option
Board Slot 1 to be used
by the peripheral bus.
OFF
OFF
According to PLC
Setup.
ON
1
2
3
4
5
6
ON
1
2
3
4
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: ......