Data Manipulation 360

block move

A function that moves data from two or more consecutive registers to a new consecutive location, keeping all the data in the same order. Also known as a file-to-file transfer.

block transfer read

A move function that immediately moves a real-world input into an input register. Found on SLC Allen Bradley PLCs.

block transfer write

A move function that tells the processor to write data from a stored register to a new location. Found on Allen Bradley PLCs.

control block length

The parameter that controls the number of registers to be moved in a Block Move function.

data manipulation

A process of altering register data so as to change output status, without altering the ladder program.

destination

The register location where data are moved or copied. The destination is where the information is going.

FIFO

The most common stacking function that unloads data in the same order it was received. FIFO stands for "first in, first out."

file

A data register in a PLC that stores bits of information. Files are often referred to as registers.

file-to-file transfer

A function that moves data from two or more consecutive registers to a new location of consecutive registers, keeping all the data in the same order. Also known as a Block Move.

FMOV

A move function that also instructs the processor to repeat the same move on a set basis. Found on Cutler-Hammer PLCs.

Get/Put

A means of data manipulation that copies data from one register. Get/Put is another name for Move.

indirect block read

A move function that tells the processor to immediately update specified registers without waiting to be scanned. Found on Modicon PLCs.

indirect block write

A move function that copies a block of data to specified nonconsecutive registers. Found on Modicon PLCs.

length parameter

The information that specifies the number of words that will be transferred during data manipulation.

LIFO

A less common stacking function that unloads data in the opposite order that it was received. LIFO stands for "last in, first out."

mask

A filter that hides certain specified bits so that they will not be acknowledged as moved.

masked move instruction

A type of data move that tells the processor to ignore certain specified bits after they have been moved.

move

A means of data manipulation that copies data from one register to another register. The Move function copies over data within the entire word, which is typically 16 bits.

register

A data file in a PLC that stores bit files.

register-to-table

A type of data move that takes one consecutive block of data from a register and copies it to various nonconsecutive individual registers. Any number of individual bits can be copied, but the total is limited by the size of the register, which is typically 16 bits.

source

The original register location of data to be moved or copied. The source is where the information originates.

stacking function

A method of data manipulation that allows you to organize data relative to time and priority.

table

A data register in a PLC that stores bits of information. The term "table" is used in place of files or registers in some PLCs.

table-to-register

A type of data move that collects bits from nonconsecutive registers and copies them into one consecutive block of data. Any number of individual bits can be copied, but the total is limited by the size of the register, which is typically 16 bits.

timer

A set of PLC instructions that automatically starts or stops machines and other devices when a preset time period has been exceeded.

word

A 16-bit unit of data that corresponds to an I/O group and stores I/O values.