Chapter 3, Chapter objectives, The function block bram functions – Rockwell Automation 1336T Function Block Prog. Manual, Series A/B User Manual

Page 49: System interactions

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Chapter 3

3–1

1336 FORCE — 5.9 August 1995

System Interactions

This chapter provides information about the following topics:

The function block BRAM functions

The power up sequence

The compiler modes and terminal operation differences

Multiple execution list copies

The task status services

The link processing faults

The performance issues that concern links

Function block applications use two kinds of memory: RAM and
BRAM.

RAM, or Random Access Memory, is the working memory area
where information is stored while the system is powered up. Any
information that is in RAM is lost when you remove the power,
perform a system reset, or performs a function block Init. When a
function block application is properly set up, the application
executes partially out of RAM and manipulates data stored in
RAM.

BRAM, or Battery backed up RAM (also known as EEPROM), is
memory which is retained when the power is removed from the
system. You can copy your function block application from RAM
to BRAM by saving it. If you save your function block
application in BRAM, it is transferred from BRAM to RAM
when the power is cycled or a drive reset occurs.

The following are descriptions of the function block Init (initialize),
function block Store (save), and function block Recall (restore)
operations.

Chapter Objectives

The Function Block BRAM
Functions

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