Allen-Bradley MicroLogix 1200 Reference Manual

Publication 1762-RM001C-EN-P
4-8 Programming Instructions Overview
Indirect Addressing Example
An equivalent example using indirect addressing is shown below. In place
of using the index register, S:24, the user can designate any other valid
word address as the indirect address. Multiple indirect addresses can be
used within an instruction.
The following ADD instruction uses an indirect address in the Source A
and Destination addresses. If the indirect offset value is 20 (stored in
N7:3), the controller uses the data stored at the base address plus the
indirect offset to perform to instruction.
In this example, the controller uses the following addresses:
Operand Base Address Offset Value in N7:3 Working Address
Source A N7:0 20 N7:20
Destination N7:0 20 N15:20
Indirect
Addresses
Working
Addresses
ADD
Add
Source A N7:[N7:3]
Source B 25
Dest N15:[N7:3]
ADD ADD
Add
Source A N7:20
Source B 25
Dest N15:20
ADD

Allen-Bradley MicroLogix 1200 Specifications

General

Series	MicroLogix 1200
Type	Programmable Logic Controller (PLC)
Mounting	DIN rail or panel mount
Programming Language	Ladder Logic
Programming Software	RSLogix 500
I/O Points	Up to 40
Communication Ports	RS-232, RS-485
Memory	6 KB user memory
Power Supply	24V DC or 120/240V AC
Expansion	Supports expansion I/O modules
Operating Temperature	0°C to 55°C (32°F to 131°F)
Dimensions	90 mm x 110 mm
Weight	0.5 kg (1.1 lbs)