GE RX3i User Manual page 118

Word Offset Value
(Word 7) EGD Command Number: Word 7 requests that a write EGD exchange operation occur. If the
command is processed successfully, it will result in data for a specified EGD exchange being written from the
client to the server.
(Word 8) Command Retry Time: Word 8 specifies the time (in milliseconds) the Ethernet Interface will wait
between retries when transferring the command. A total of four tries will be made to send the command. If no
response is received after the four tries (i.e. after four times the retry time value), an error status will be returned
in the COMMREQ status word. If the command retry is specified as zero, the default value of one second is used.
(Word 9) Local PLC - Memory Type: Words 9-11 specify the location in the local PLC where the Ethernet
Interface will get the data to write to the remote EGD device. Valid values for Word 9 are listed in the
description of Read PLC Memory Command. The amount of data to be transferred is specified by the Exchange
Data Length (Word 18).
(Words 10 - 11) Local PLC - Memory Starting Address: Words 10 and 11 determine the starting address in the
local PLC from which data is to be written to the remote EGD exchange. The value entered is the 32-bit offset
(1-based) from the beginning of PLC memory for the memory type and mode specified in Word 9. Word 10
contains the least significant 16 bits of the offset; word 11 contains the most significant 16 bits of the offset.
This offset will be either in bits, bytes, or words depending on the mode specified. (For example, if Word 9=16
and Words 10,11 = 2, 0 then the starting address will be %I9.) Valid ranges of values depend on the PLC's
memory ranges.
(Word 12) Remote EGD exchange – Exchange Signature: Words 12 contains the 16-bit exchange signature
value to be compared at the remote EGD device. For remote PLCs, the exchange signature should be set to
zero if signatures are not being used. However, when signatures are enabled, the signature field can be set to a
non-zero value so that commands will only be executed if signatures match. In this case, mismatched
signatures will cause the command to return a failure status.
An EGD signature has the format maj.min, where maj is the major value and min is the minor value. The least
significant byte of this word indicates the minor value and the most significant byte indicates the major value.
For example, a value of 0xAABB refers to a maj.min value of 0xAA.0xBB.
EGD Signatures Enabled
(Y/N)
No
Yes
Yes
(Words 13 - 14) Remote EGD exchange – Producer ID: Words 13 and 14 contains the 32-bit Producer ID of the
desired exchange at the remote EGD device. Word 13 contains the least significant 16 bits of the Producer ID;
word 14 contains the most significant 16 bits.
(Words 15 - 16) Remote EGD exchange – Exchange ID: Words 15 and 16 contains the 32-bit Exchange ID of
the desired exchange at the remote EGD device. Word 15 contains the least significant 16 bits of the Exchange
ID; word 16 contains the most significant 16 bits. For the Write EGD Command, the exchange at the remote
device must be a Produced exchange.
(Word 17) Remote EGD exchange – Exchange Data Offset: Word 17 contains the 0-based byte offset of the
data to be overwritten in the data portion of the exchange at the remote EGD device.
(Word 18) Remote EGD exchange – Exchange Data Length: Word 18 contains the length (in bytes) of the
exchange data to be written to the remote EGD device. The exchange data length may not exceed 1400 bytes
or the amount of memory available in the PLC for the selected memory type, whichever is less.
(Word 19) Remote Server - Network Address Type: Word 19 specifies the format of the remote PLC address.
Word 19 must contain the value 1. This indicates a dotted-decimal IP address expressed using a separate
register for each decimal digit.
GFK-2224Q
Description
Signature Comparison
Desired
No
No
Yes
January 2017
Chapter 6. Programming EGD Commands
Recommended with
RMS of EGD
No
No
Yes
User Specified
Signature
0 (Default - no check)
0 (Default - no check)
Current EGD signature
105