Allen-Bradley LOGIX 5000 Reference Manual page 309

Drives
UPDN Structure
Input Parameter
EnableIn
Initialize
InitialValue
InPlus
InMinus
Hold
Output Parameter
EnableOut
Out
Structured Text
Operand Type
UPDN tag UP_DOWN_ACCUM
See Structured Text Syntax for more information of the syntax of expressions
within structured text.
Rockwell Automation Publication 1756-RM006K-EN-P - November 2018
Data Type Description
BOOL Enable input. If cleared, the instruction
does not execute and outputs are not
updated.
Default is set.
BOOL The initialize input request for the
instruction. When Initialize is set, the
instruction sets Out and the internal
accumulator to InitialValue.
Default is cleared.
REAL The initialize value of the instruction.
Valid = any float
Default = 0.0
REAL The input added to the accumulator.
Valid = any float
Default = 0.0
REAL The input subtracted from the
accumulator.
Valid = any float
Default = 0.0
BOOL The hold input request for the
instruction. When Hold is set and
Initialize is cleared, Out is held.
Default is cleared.
Data Type Description
BOOL Indicates if instruction is enabled.
Cleared to false if Out overflows.
REAL The output of the instruction.
Format Description
Structure UPDN structure
Chapter 2
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