Omron CJ - INSTRUCTIONS REFERENCE MANUAL 07-2009 Reference Manual page 184

Note Observe the following precaution when using UP(521) and DOWN(522) in a subroutine.
• The operation of UP(521) and DOWN(522) will not be consistent if the same subroutine is executed
more than once in the same cycle.
• An subroutine will not be executed while the input condition for the subroutine is OFF. Caution is thus
required when using UP(521) and DOWN(522) in a function block definition. For details, refer to
information on SBS(091).
Sample program
UP
0.00
DOWN
0.00
CS/CJ/NSJ Series Instructions Reference Manual (W474)
i
0.01
When CIO 0.00 goes from OFF to ON, CIO
0.01 is turned ON for just one cycle.
0.00
0.01
Cycle
time
i
0.01
When CIO 0.00 goes from ON to OFF, CIO
0.01 is turned ON for just one cycle.
0.00
0.01
3. Instructions
Cycle
time
3
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