Sequencer Input (Sqi); Relay Ladder; Control Structure - Allen-Bradley Logix5000 Reference Manual

Chapter 10 Sequencer Instructions (SQI, SQO, SQL)

Sequencer Input (SQI)

Mnemonic Data Type
.ER BOOL
.LEN DINT
.POS DINT
436
The SQI instruction detects when a step is complete in a sequence pair of SQO/
SQI instructions.
Operands:

Relay Ladder

Operand
Array
Mask
Source
Control
Length
Position

CONTROL Structure

Description
The error bit is set when .LEN ≤ 0, .POS < 0, or .POS > .LEN.
The length specifies the number of steps in the sequencer array.
The position identifies the element that the instruction is currently comparing.
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Type Format Description
DINT Array tag Sequencer array
Specify the first element of the sequencer array
Do not use CONTROL.POS in the subscript
SINT Tag Which bits to block or pass
INT Immediate
DINT
A SINT or INT tag converts to a DINT value by sign-extension.
SINT Tag Input data for the sequencer array
INT
DINT
A SINT or INT tag converts to a DINT value by sign-extension.
CONTROL Tag Control structure for the operation
Typically use the same CONTROL as the SQO and
SQL instructions
DINT Immediate Number of elements in the Array (sequencer table)
to compare
DINT Immediate Current position in the array
initial value is typically 0