Rockwell Automation 1336T Function Block Prog. Manual, Series A/B - Manual (Page 117)

Chapter 5
5–1
1336 FORCE — 5.9 August 1995
Block Transfer Services
In this chapter, you will read about:
❒ Block transfer descriptions
❒
Block transfer status word
❒ Individual block transfer services descriptions
This chapter contains the message descriptions that you need to set
up data files for the block transfer services using an Allen-Bradley
PLC or SLC-500 (using a 1747 SN adapter with an SLC 503 or 504).
Each block transfer message contains a three word command header
and a data buffer:
Header Word 1
Header Word 2
Header Word 3
Data Word 4
The first three words of a message make up the message header, and
are common to all RIO messages with the 1336T PLC
Communications Adapter Board.
Header word 1 is zero.
Header words 2 and 3 specify which operation you want to perform.
Header and data values vary depending on the operation you are
performing. Also included is a description of the status word that is
returned from the drive and appears in the Block Transfer Read
Header.
Note: The sawtooth generator application presented in Chapter 1 is
an example of using the block transfer services.
Chapter Objectives
Block Transfer
Descriptions
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