Rockwell Automation 1772-LP3 PLC - 2/30 Programmable Controller Programming and Operations Manual - Manual (Page 260)

Bit Shifts
Chapter 14
14Ć8
This condition instruction examines a user specified bit in a bit shift
register, such as shown in Figure 14.1, for an on or 1 condition. The
instruction can be used alone or in conjunction with other input
instructions to affect the rung decision.
Instruction overview:
Input instruction
Key sequence: [SHIFT REG] 19
3 words of users program required
To program an Examine On Shift Bit instruction press [SHIFT REG] 19.
A display represented by Figure 14.6 will appear.
Figure 14.6
EXAMINE ON SHIFT BIT Format
EXAMINE ON
SHIFT BIT
FILE: 110
BIT NO.: 001
Numbers shown are default values. Bold numbers must be replaced by userĆentered values. The number of default address digits
initially displayed Ċ 3, 4, or 5 Ċ will depend on the size of the data table. Initially displayed default values are governed by the I/O rack
configuration.
FILE : Starting address of the file (file of bit shift instruction).
BIT NUMBER : Decimal number of the bit to be examined (1Ć999).
Figure 14.7 shows the format of Figure 14.6 for the following conditions
of the bit shift register of Figure 14.1.
File – Starts at word 400
Bit No. – Examine bit number 67 in the shift register for an on (1)
condition.
14.4
Examine On Shift Bit
14.4.1
Programming Examine On
Shift Bit Instruction