7

Reserved References

In a GMR system, the following references are reserved or assigned special functions:

References

Reserved For:

 

 

%I0001 to %I1024 (788 CPU)

Input Table. Some references are automatically assigned by

%I00001 to %I12288 (789 CPU)

the GMR Configuration Software. Others are available for

 

use, as explained in this chapter.

 

 

%Q0001 to %Q1024 (788 CPU)

Output Table. Some references are automatically assigned by

%Q00001 to %Q12288 (789 CPU)

the GMR Configuration Software. Others are available for

 

applicationuse.

 

 

%AI0001 to %AImax

The length of %AI data (shown at left as max ) is configur-

 

able. Some references are automatically assigned by the

 

GMR software. Others are available for application use.

 

 

%Rmax± 320+ (66xN) to %Rmx

The length of %R data is configurable. At left, the letter N rep-

 

resents the number of bus controllers on the bus.

 

The GMR software requires the use of several areas of %R

 

memory, as detailed in this chapter.

 

 

%G0001 to %G0896

The GMR software provides these memory areas for applica-

%GA0001 to %GA0896

tion global data transfer. The correct method of program-

%GB0001 to %GB0896

ming global data in a GMR system is described in this chap-

%GC0001 to %GC0896

ter.

 

 

%M12225 to %M12256

System status bits

 

 

%M12257 to %M12288

Systemcontrolflags

 

 

%R0001 to %R0256

%R startup initialization data from another online PLC.

(defaults: starting reference and

References shown at left are the defaults; refer to your GMR

lengthareconfigurable)

configuration printout for the actual references used.

 

 

%R0257 to %R0272

%M startup initialization data from another PLC. Refer-

(defaults: starting reference is con-

ences shown at left are the defaults; refer to your GMR con-

figurable)

figuration printout for the actual references used.

 

%M defaults to 16 words long.

 

 

Memor y Write Access

With the exceptions noted above, the following memory areas can be written to if Write

Access is enabled during GMR configuration:

%R

Registers

%AI

Analog Input Table

%AQ

Analog Output Table

%I

Discrete Input Table

%Q

Discrete Output Table

%T

Temporary internal reference bits that are not saved through power loss

%M

Internal reference bits that are saved through power loss

%G

Global Data memory

%GD

Global Data memory

%GE

Global Data memory

For discrete (bit) memories: %I, %Q, %T, and %M, the starting reference must be on a byte boundary 1, 9, 17, etc). Global Data %GA, %GB, and %GC memories are not available. Those memory areas are used by the GMR system to exchange data (see above), and cannot be accessed directly.

Page 6-23 describes configuration for setting up Write Access.

7-4

GeniustModular Redundancy Flexible Triple Modular Redundant (TMR) System

GFK-0787B

 

User's Manual ± March 1995

 

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