Write Egd Exchange (4003); Write Egd Exchange Command Block - GE RX3i User Manual

Chapter 6. Programming EGD Commands

Write EGD Exchange (4003)

6.8
The Write EGD Exchange command can be used to write portions of a configured Ethernet Global Data
exchange in a remote producer node. EGD protocol prohibits writing to a consumed exchange. This command
identifies the exchange to be written using its configured Producer ID and Exchange ID. It can then write the
content of that data directly to the device memory. This command can be sent to PACSystems PLCs and to
other EGD Class 2 devices. In a PACSystems PLC, writing an EGD exchange modifies the PLC reference memory
locations configured for transfer at the specified offset in the exchange. Thus current process data will be
updated, not the data that was transferred last in the exchange.

Write EGD Exchange Command Block

Word Offset Value
Word 1 Length of command data
block
Word 2 0
Word 3 (See table on page 95)
Word 4 0-based
13
Word 5 0
Word 6 0
Word 7 4003 (fa3H)
Word 8 Retry time, in milliseconds
Word 9 Local write buffer memory
type
Word 10 Local write buffer reference
table starting address (least
significant word)
Word 11 Local write buffer reference
table starting address (most
significant word)
Word 12 Remote signature
Word 13 Remote Producer ID (least
significant word)
Word 14 Remote Producer ID (most
significant word)
Word 15 Remote Exchange ID (least
significant word)
Word 16 Remote Exchange ID (least
significant word)
Word 17 Remote Exchange Offset
Word 18 Write length
Word 19 Network address type
Word 20 Network address length
Word 21 to IP Address of the remote PLC
Word 24
Word 25 Reserved
104 PACSystems* RX7i & RX3i TCP/IP Ethernet Communications User Manual
Description
Always 19
Always 0 (no-wait mode request)
Memory type of COMMREQ Status Word
Offset of COMMREQ Status Word
Reserved
Reserved
Write EGD Exchange command number.
The time between retries of command transfers. Default is
1000ms.
Memory type for the data, in the local PLC.
1-based offset
EGD Exchange signature. This should be 0 for PLCs when not
using signatures. If run-mode store of EGD will be used, the
use of signatures is highly recommended.
EGD Producer ID
EGD Exchange ID
Byte offset (0-based) in the exchange that should be read.
Number of bytes to be written in the range 0 to 1400 bytes.
Must be 1. Indicates an IP address will be used.
Must be 4 for IP address.
Group ID (multicast) is not permitted.
Four integers, specified as one integer per word of the dotted-
decimal IP address of the remote PLC. May not be a group IP
address.
Always 0
GFK-2224Q