ProSoft Technology MVI69-EGD - Manual (Page 70)

MVI69-EGD ♦ CompactLogix or MicroLogix Platform Reference
GE Ethernet Global Data Communication Module
Page 70 of 96 ProSoft Technology, Inc.
November 3, 2008
Packet
Info Description Data
State: 24 4 0x HH HH HH HH
Exchange Length: 28 4 0x HH HH HH HH
Message Count: 32 4 0x HH HH HH HH
Missed Count: 36 4 0x HH HH HH HH
Refresh Error Count: 40 4 0x HH HH HH HH
Reserved: 44 4 0x HH HH HH HH
Command NAK PDU
PDU Type = 18
Command NAK Response.
The command NAK response may be sent by a responder to any command
received on the command port that is in error. Use of the command NAK allows
the responder to give more precise and detailed information about the nature of
the error to the requester. The command NAK shall not be sent in response to a
NAK message.
The NAK message is returned to indicate a syntactic error in a request message.
It should only be used if the request is unintelligible. Thus, whenever possible,
the corresponding response to a received request message shall be returned.
Packet
Info Description Data
Source Port: 7937 (0x 1F01)
Destination Port: 7937 (0x 1F01)
Length: xx bytes (0x 00 XX)
Checksum: xxxxx (0x XX XX)
EGD's PDU Field: Offset Bytes Hex code
PDU Type: 0 1 0x 12
Message Flag: 1 1 0x HH
Request ID: 2 2 0x HH HH
PVN1: 4 1 0x 01
Status: 5 1 0x HH
Message Length: 6 2 0x HH HH
Producer ID: 8 4 0x HH HH HH HH
Exchange ID: 12 4 0x HH HH HH HH
UDP
EGD:
Error Code: 16 2 0x HH HH
Reserved: 18 2 0x HH HH
Offending
Message: 20 16 0x HH . . . HH
Error String:
(up to 80
characters)
36 XX 0x HH . . . HH