Difd - Omron CJ - REFERENCE MANUAL 02-2010 Reference Manual

3. Instructions

DIFD

Instruction
DIFFERENTIATE DOWN
Symbol
Applicable Program Areas
Function block
Area
definitions
Usage OK
Operands
Operand
B Bit
Operand Specifications
Word addresses
Area
CIO WR HR
B OK OK OK
*1 CJ2 CPU Units only.
Flags
No flags are affected by DIFD(014).
Function
When the execution condition goes from ON
to OFF, DIFD(014) turns B ON. When
DIFD(014) is reached in the next cycle, B is
turned OFF.
Hint
• DOWN(522) can be used to execute an instruction for just one cycle when the execution condition
goes from ON
• The operation of DIFD(014) depends on the execution condition for the instruction itself as well as the
execution condition for the program section when it is programmed in an interlocked program section,
a jumped program section, or a subroutine.
• DIFD(014) has immediate refreshing variation (!DIFD(014)). When an external output bit has been
specified for B in this instruction, any changes to B will be refreshed when the instruction is executed
and reflected immediately in the output bit. (The changes will not be reflected immediately if the bit is
allocated to a Group-2 High-density I/O Unit, High-density Special I/O Unit, or a Unit mounted in a
SYSMAC BUS Remote I/O Slave Rack.)
166
Mnemonic Variations
DIFD !DIFD
Block program areas Step program areas
Not allowed OK
Description
AR T C DM EM
1 1
OK --- ---
OK* OK*
OFF.
Function
code
DIFD(014) turns the designated bit ON for one
014 cycle when the execution condition goes from ON
to OFF (falling edge).
DIFD
DIFD(014)
B
B: Bit
Subroutines
OK
Data type
BOOL
Indirect DM/EM
addresses
Con-
stants
@DM *DM
DR
@EM *EM
--- --- --- ---
Execution condition
Status of B
CS/CJ/NSJ Series Instructions Reference Manual (W474)
Function
SFC action or transition
Interrupt tasks
programs
OK OK
Size
---
Registers Flags
Pulse
bits
Indirect
IR TK CF
using IR
--- OK --- ---
1 cycle
TR
bits
--- ---