GE RX3i

Chapter 6. Programming EGD Commands
GFK-2224Q January 2017 95
Enable: Control logic for activating the COMMREQ Function Block.
IN: The location of the Command Block. The Command Block contains the parameters of the COMMREQ
request. It can be located at any valid address within a word-oriented memory area (%R, %AI, %AQ, %P, %L, or
%W) in the PACSystems PLC. Parameters for the EGD commands are described on the following pages.
SYSID: A hexadecimal word value that gives the rack (high byte) and slot (low byte) location of the Ethernet
Interface. For example, an Ethernet Interface in rack zero, slot six would use the value 6 for this parameter. For
the PACSystems CPU embedded Ethernet interface, enter the rack/slot location of the CPU module.
TASK: For the PACSystems CPU embedded Ethernet interface, Task must be set to the value 65536 (10000H) to
address the CPU’s Ethernet daughterboard. For a PACSystems Ethernet module, Task must be set to zero.
FT Output: The FT output is set if the PLC CPU is unable to deliver the COMMREQ to the Ethernet interface.
When the FT output is set, the Ethernet Interface is unable to return a COMMREQ status word to the PLC logic
application.
6.4 COMMREQ Status for the EGD Commands
Words 3 and 4 of every COMMREQ Command Block specify a memory type and location to receive status
information about the execution of the command.
Word 3 specifies the memory type for the COMMREQ status word. The memory types are listed in the table
below:
Type
Value
(Decimal)
Value
(Hex.) Description
%R 8 08H Register memory (word mode)
%AI 10 0AH Analog input memory (word mode)
%AQ 12 0CH Analog output memory (word mode)
%I 16
70
10H
46H
Discrete input memory (byte mode)
Discrete input memory (bit mode)
%Q 18
72
12H
48H
Discrete output memory (byte mode)
Discrete output memory (bit mode)
%T 20
74
14H
4AH
Discrete temporary memory (byte mode)
Discrete temporary memory (bit mode)
%M 22
76
16H
4CH
Discrete momentary internal memory (byte mode)
Discrete momentary internal memory (bit mode)
%G 56
86
38H
56H
Discrete global data table (byte mode)
Discrete global data table (bit mode)
%W 196 C4H Word memory (word mode; limited to %W1-%W65536)
Word 4 of the COMMREQ Command Block specifies the offset within the memory type selected. The status
word address offset is a zero-based number. For example, if %R1 should be the location of the status word,
you must specify a zero for the offset. The offset for %R100 would be 99 decimal. (When using %W memory,
the maximum offset value that can be entered is 65535, signifying %W65536.)
COMMREQ Status Values
The Ethernet Interface reports the status of the COMMREQ back to the status location. See Chapter 12,
Diagnostics, for COMMREQ status values that may be reported for the EGD commands.