17
Function Blocks
Section 1-4
1-4
Function Blocks
Function blocks can be used in programming SYSMAC CP-series PLCs.
1-4-1
Overview of Function Blocks
A function block is a basic program element containing a standard processing
function that has been defined in advance. Once the function block has been
defined, the user just has to insert the function block in the program and set
the I/O in order to use the function.
As a standard processing function, a function block is not created with actual
physical addresses, but local variables. The user sets parameters (addresses
or values) in those variables to use the function block. The addresses used for
the variables themselves are automatically assigned by the system (CX-Pro-
grammer) each time they are placed in the program.
In particular, each function block is saved by the CX-Programmer as an indi-
vidual file that can be reused with programs for other PLCs. This makes it
possible to create a library of standard processing functions.
cc
aa
bb
#0000
MOV
dd
Standard program
section written
with variables
Function block A
Define in advance.
Insert in program.
Save function
block as file.
Library
Function
block A
Reuse
To another PLC program
Program 1
Copy of function block A
Input
Variable
Variable
Output
Setting
Setting
Copy of function block A
Input
Variable
Variable
Output
Program 2
Copy of function block A
Variable
Output
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...
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