Allen-Bradley MicroLogix 1200 Reference Manual

Publication 1762-RM001C-EN-P
21-30 Communications Instructions
Example 1 - Local Read from a 500CPU
Message Instruction Setup
In this example, the controller reads 10 elements from the target’s (Local
Node 2) N7 file, starting at word N7:50. The 10 words are placed in the
controller’s integer file starting at word N7:0. If five seconds elapse before
the message completes, error bit MG11:0/ER is set, indicating that the
message timed out.
Valid File Type Combinations
Valid transfers between file types are shown below for MicroLogix
messaging:
Local Data Types Communication Type Target Data Types
O
(1)
, I
(1)
, B, N, L
(1) Output and input data types are not valid local data types for read messages.
<---> read/write O, I, S, B, N, L
T <---> read/write T
C <---> read/write C
R <---> read/write R
RTC
(2)
(2) 500CPU write RTC-to-Integer or RTC-to-RTC only. Applies to MicroLogix 1200 Series B
and later, and 1500 Series B and later only.
---> write N, RTC

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)