HE693DNT250 User Manual-DeviceNET Master

HE693DNT250 User Manual-DeviceNET Master
User Manual for the
HE693DNT250
DeviceNet Master
(Scanner)
Fourth Edition
June 23, 2000
MAN0054-04
PREFACE
23 JUN 2000
PAGE 3
PREFACE
This manual explains how to use the Horner APG’s DeviceNet Master (Scanner). .
Copyright (C) 2000 Horner APG, LLC., 640 North Sherman Drive, Indianapolis, Indiana 46201. All
rights reserved. No part of this publication may be reproduced, transmitted, transcribed, stored in a
retrieval system, or translated into any language or computer language, in any form by any means,
electronic, mechanical, magnetic, optical, chemical, manual or otherwise, without the prior agreement
and written permission of Horner APG, LLC.
All software described in this document or media is also copyrighted material subject to the terms and
conditions of the Horner Software License Agreement.
Information in this document is subject to change without notice and does not represent a
commitment on the part of Horner APG, LLC.
DeviceNet is a trademark of Open DeviceNet Vendors Association (ODVA).
Logicmaster, LM90, and SNP are trademarks of GE Fanuc
Windows and Windows-95 are trademarks of Microsoft Corporation
For user manual updates, contact Horner APG, Technical
Support Division, at (317) 916-4274 or visit our website at
www.heapg.com.
PAGE 4
23 JUN 2000
PREFACE
LIMITED WARRANTY AND LIMITATION OF LIABILITY
Horner APG, LLC. ("HE") warrants to the original purchaser that the DeviceNet Master (Scanner)
manufactured by HE is free from defects in material and workmanship under normal use and service.
The obligation of HE under this warranty shall be limited to the repair or exchange of any part or parts
which may prove defective under normal use and service within two (2) years from the date of
manufacture or eighteen (18) months from the date of installation by the original purchaser whichever
occurs first, such defect to be disclosed to the satisfaction of HE after examination by HE of the
allegedly defective part or parts. THIS WARRANTY IS EXPRESSLY IN LIEU OF ALL OTHER
WARRANTIES EXPRESSED OR IMPLIED INCLUDING THE WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR USE AND OF ALL OTHER OBLIGATIONS OR
LIABILITIES AND HE NEITHER ASSUMES, NOR AUTHORIZES ANY OTHER PERSON TO
ASSUME FOR HE, ANY OTHER LIABILITY IN CONNECTION WITH THE SALE OF THIS
DEVICENET MASTER (SCANNER). THIS WARRANTY SHALL NOT APPLY TO THIS DEVICENET
MASTER (SCANNER) OR ANY PART THEREOF WHICH HAS BEEN SUBJECT TO ACCIDENT,
NEGLIGENCE, ALTERATION, ABUSE, OR MISUSE. HE MAKES NO WARRANTY WHATSOEVER
IN RESPECT TO ACCESSORIES OR PARTS NOT SUPPLIED BY HE. THE TERM "ORIGINAL
PURCHASER", AS USED IN THIS WARRANTY, SHALL BE DEEMED TO MEAN THAT PERSON
FOR WHOM THE DEVICENET MASTER (SCANNER) IS ORIGINALLY INSTALLED. THIS
WARRANTY SHALL APPLY ONLY WITHIN THE BOUNDARIES OF THE CONTINENTAL UNITED
STATES.
In no event, whether as a result of breach of contract, warranty, tort (including negligence) or
otherwise, shall HE or its suppliers be liable of any special, consequential, incidental or penal
damages including, but not limited to, loss of profit or revenues, loss of use of the products or any
associated equipment, damage to associated equipment, cost of capital, cost of substitute products,
facilities, services or replacement power, down time costs, or claims of original purchaser's
customers for such damages.
To obtain warranty service, return the product to your distributor with a description of the
problem, proof of purchase, post paid, insured and in a suitable package.
ABOUT PROGRAMMING EXAMPLES
Any example programs and program segments in this manual or provided on accompanying
diskettes are included solely for illustrative purposes. Due to the many variables and requirements
associated with any particular installation, Horner APG cannot assume responsibility or liability for
actual use based on the examples and diagrams. It is the sole responsibility of the system designer
utilizing the to appropriately design the end system, to appropriately integrate the DeviceNet Master
(Scanner) and to make safety provisions for the end equipment as is usual and customary in
industrial applications as defined in any codes or standards which apply. It assumed that the system
designer is familiar with PLC programming and configuration.
Note: The programming examples shown in this manual are for illustrative
purposes only. Proper machine operation is the sole responsibility of the
system integrator.
PREFACE
23 JUN 2000
PAGE 5
Revisions to this Manual
This version (MAN0054-04) of the DeviceNet User Manual contains the following revisions,
additions, and deletions:
1.
Revised Section 1.1 and 1.2 to include UCMM protocol and all four Message Body
Format under UCMM.
2.
Moved Chapter 3: “Configuration” to Chapter 6. Replaced Chapter 3 with
“DeviceNet Node, DNT250 & PLC Relationships.”
3.
Replaced Chapter 4: “DeviceNet to PLC I/O Mapping” with a new Chapter 4:
“DNT250 Status and Command Data Assemblies.”
4.
Replaced Chapter 5: “HE693DNT250 Network Operation” with a new Chapter 5:
“Explicit Messaging Using the DNT250.”
5.
Added new configuration software to Chapter 6: Configuration.
6.
Deleted Sections 7.3 and 7.4. Moved Table 7.1: General Error Codes to Appendix C.
7.
Replaced Appendix A with “DNT250 Network Operation.”
8.
Replaced Appendix B with “Packet Timing.”
PAGE 6
23 JUN 2000
PREFACE
TABLE OF CONTENTS
PREFACE ...................................................................................................................................3
LIMITED WARRANTY AND LIMITATION OF LIABILITY..............................................................4
ABOUT PROGRAMMING EXAMPLES........................................................................................4
TABLE OF CONTENTS...............................................................................................................6
CHAPTER 1: INTRODUCTION ..................................................................................................7
1.1
Overview ...................................................................................................................... 7
1.2
HE693DNT250 Features .............................................................................................. 7
1.3
Technical Specifications ............................................................................................... 8
CHAPTER 2: INSTALLATION ....................................................................................................9
2.1
Connectors ................................................................................................................... 9
2.1.1
RS-485 Connector ................................................................................................. 9
2.1.2
DeviceNet I/O Connector ....................................................................................... 9
2.2
LED Indicators.............................................................................................................10
CHAPTER 3: DEVICENET NODE, DNT250 & PLC RELATIONSHIPS......................................13
3.1
General .......................................................................................................................13
3.2
Module to PLC Register Mapping ................................................................................13
3.3
Node to PLC Register Mapping....................................................................................13
3.4
Message Packets and Fragmentation ..........................................................................13
3.5
Physical Limitations .....................................................................................................13
3.6
Data Assemblies..........................................................................................................14
3.7
DNT250 Configuration Introduction ..............................................................................15
CHAPTER 4: DNT250 STATUS AND COMMAND DATA ASSEMBLIES....................................17
4.1
Register Requirements and Definitions of Data Assemblies .........................................17
CHAPTER 5: EXPLICIT MESSAGING USING THE DNT250 ....................................................21
5.1
General .......................................................................................................................21
5.2
Explicit Messages and the DNT250 .............................................................................21
5.3
Building Explicit Messages...........................................................................................22
5.4
How to Interpret Explicit Response Messages..............................................................24
5.5
Explicit Message Errors ...............................................................................................24
CHAPTER 6: CONFIGURATION ..............................................................................................25
6.1
General .......................................................................................................................25
6.2
DNT250 Module Configuration.....................................................................................25
6.3
PLC Rack Configuration ..............................................................................................26
6.4
DNT250 Configurator...................................................................................................27
6.4.1
General ................................................................................................................27
6.4.2
Configuration Procedures ....................................................................................28
CHAPTER 7: DEVELOPING USER SOFTWARE .....................................................................37
7.1
Software Support for the Polled Connection.................................................................37
7.2
Software Support for the Explicit Connection ...............................................................37
APPENDIX A: DNT250 NETWORK OPERATION.....................................................................39
1 Sequence of Events ........................................................................................................39
2 Establishing a Connection ...............................................................................................39
APPENDIX B: PACKET TIMING...............................................................................................41
1 Message Packet Timing ..................................................................................................41
2 Network Scan Time versus PLC Scan Time ....................................................................41
APPENDIX C: DEVICENET GENERAL ERROR CODES .........................................................43
CH.1: INTRODUCTION
23 JUN 2000
PAGE 7
CHAPTER 1: INTRODUCTION
1.1
Overview
The HE693DNT250 DeviceNet Scanner (DNT250) is an intelligent communications interface
module that provides DeviceNet Scanner functionality to a GE Fanuc Series 90-30 PLC. The
DNT250 allows the connection of up to 63 DeviceNet slave nodes. Depending on baud rate and
the cable type used, the DeviceNet nodes may be located up to 1,500 feet from the PLC.
The DNT250 Polled data is mapped directly into the PLC's %I, %Q, %AI and %AQ registers. The
ladder programmer can treat the DNT250 and its attached DeviceNet nodes as a large I/O
module. Polled data is transferred between the DNT250 and the PLC using Backplane I/O which
is fast and efficient.
The DNT250 provides two additional constructs known as Ladder Code Initiated Explicit
Messaging (LIEM) and the Unconnected Message Manager (UCMM).
The LIEM allows the ladder code executing within the PLC to initiate dialogues with DeviceNet
nodes through the use of explicit messaging. This enables the PLC to access data beyond that
normally available using the Polled Connection. For LIEM, data is transferred between the
DNT250 and the PLC using a technique known as Backplane Mail. Backplane Mail requires
considerably more processing time than Polled messaging. LIEM should therefore only be used
to access infrequently required data such as device configuration and tuning parameters.
The DeviceNet specification provides two methods of establishing communications between
scanners and nodes. The first is known as “Group 2 Only”. This was the only method provided by
older DNT250s. The second method makes use of the “Unconnected Message Manager”
(UCMM). The new DNT250 allows both of these methods to be used simultaneously. Any single
slave device on a DeviceNet network can be either a Group 2 Only node or a UCMM node, never
both. A DeviceNet network can be made up of a mixture of “Group 2 Only” and UCMM” slave
devices.
The “Group 2 Only” method is by far the simplest. Because the UCMM is a far more intense
protocol, very few manufactures supported it in the early days of DeviceNet. Times have
changed. Now a large percentage of DeviceNet manufactures support the UCMM. As a result,
the DNT250 has been upgrade to support both the UCMM and Group 2 Only protocols.
1.2
HE693DNT250 Features
The DNT250 allows a GE Fanuc Series 90-30 PLC to supervise a DeviceNet network. From the
viewpoint of the ladder program running in the PLC, the DNT250 appears as a single, very high
density I/O module.
The DNT250 supports the following DeviceNet features:
Baud Rates: 125K, 250K, and 500K,
UCMM protocol,
Group 2 Only protocol,
The Polled Connection,
The LIEM (explicit messaging),
Fragmentation on both polled and explicit connections,
All four Message Body Formats under UCMM.
When using Polled Messaging, data is read from the PLC’s %Q and %AQ registers by the
DNT250, formatted into DeviceNet packets and sent to the DeviceNet nodes. Likewise, data
produced by the DeviceNet nodes is received by the DNT250, converted into PLC register
notation and passed to the PLC's %I and %AI registers. This happens automatically without the
need for block move, "COMREQ", or other ladder program instructions.
PAGE 8
23 JUN 2000
CH.1: INTRODUCTION
The ladder code running in the PLC can build Explicit Messages to access any network data that
is known to be available through the node’s Explicit Connection. See chapter 4 for more
information on LIEM or explicit messaging.
1.3
Technical Specifications
The following HE693DNT250 DeviceNet Interface Module specifications are subject to change
without notice.
Table 1.1 - H3693DNT250 Specifications
DeviceNet Network Specifications
Parameter
Minimum Maximum
DeviceNet Power Voltage
11
25
DeviceNet Power Load
65
DeviceNet Signal Baud Rate
125
500
DeviceNet Signal Driver Fanout
0
63
PLC Power Load Specifications
Parameter
Minimum Maximum
+5Vdc (LOGIC)
0
175
+24Vdc (RELAY)
0
0
+24Vdc (ISOLATED)
0
0
Environmental Specifications
Parameter
Minimum Maximum
Operating Temperature
0
+60
Storage Temperature
-40
+85
Humidity (non-condensing)
5
95
Units
V
mA
KHz
Devices
Units
mA
mA
mA
Units
Deg C
Deg C
% RH
CH. 2: INSTALLATION
23 JUN 2000
PAGE 9
CHAPTER 2: INSTALLATION
2.1
Connectors
2.1.1
RS-485 Connector
The RS485 port allows the DNT250 to be connected to an RS-232 serial port of a PC. The port is
physically and electrically identical to that used on the GE Fanuc Series 90-30. It allows the
same cable and same PC serial port to be used to program both the PLC and the DNT250. The
DNT250 does not accept SNP or Logicmaster commands. The DNT250 must be configured using
the DN250CFG.EXE program.
IMPORTANT: Do not attempt to "talk to" the DNT250 using Logicmaster or SNP Protocol.
Although no physical damage will result, the information in the DNT250 could be corrupted such
that the DNT250 would appear "dead." A factory update could possibly be required to return the
unit to normal operating conditions
To connect the DNT250 to a PC, the user must have an SNP adapter and a straight through 9 pin
serial cable. The RS-485 port consists of a 15-pin female D-connector with the following pin
descriptions:
Table 2.1 - Configuration Port Pinouts
Pin Signal
Description
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
2.1.2
FGND
DCDDCD+
-HHP
+5V
RTSGND
CTS+
RT
RXDRXD+
TXDTXD+
RTS+
CTS-
Frame Ground
Data Carrier Detect Data Carrier Detect +
Hand Held Programmer Detect
RS485-RS232 Adapter Power
Request to Send Signal Ground
Clear to Send +
Receiver Termination
Received Data Received Data +
Transmit Data Transmit Data +
Request to Send +
Clear to Send -
1
9
8
15
Figure 2.1 – Configuration Port
(As Viewed from Front of Module)
DeviceNet I/O Connector
The DeviceNet I/O connector consists of a 5-pin removable screw terminal with the following terminal
descriptions:
Table 2.2 - DeviceNet I/O Connector
Pinout
Pin Signal Description
1
2
3
4
5
VCAN_L
Drain
CAN_H
V+
Power Signal Shield
Signal +
Power +
5
4
3
2
1
Figure 2.2 - DeviceNet I/O
Connector
(As Viewed from Front of Module)
PAGE 10
23 JUN 2000
HE693DNT250
CH. 2: INSTALLATION
Other DeviceNet devices
5
4
3
2
1
CAN_L (BLUE)
CAN_H (WHITE)
SHIELD
V+ (RED)
V- (BLACK)
Figure 2.3 - DeviceNet Wiring
A user-supplied 121Ω ¼W 1% resistor is needed for termination at EACH END of the network
cabling. Refer to the DeviceNet cabling specifications for proper location of the terminating resistor.
Table 2.3 - DeviceNet Cable Length vs Network Baud Rate
Maximum Cable Distance
DeviceNet Baud Rate
Thick Cable
Thin Cable
125KHz
1640 Feet
320 Feet
250KHz
820 Feet
320 Feet
500kHz
320 Feet
320 Feet
Maximum Drop Distance
DeviceNet Baud Rate
Per Drop
Cumulative
125KHz
20 Feet
500 Feet
250KHz
20 Feet
250 Feet
500kHz
20 Feet
120 Feet
2.2
LED Indicators
The HE693DNT250 provides two bi-color (Red/Green) diagnostic LEDs on its front panel.
DeviceNet
MS
NS
Figure 2.4 - LEDs
CH. 2: INSTALLATION
23 JUN 2000
PAGE 11
Table 2.4 - Status Indicator States and Meaning
Module Status LED (MS)
Module Status
For this state
Condition
LED is
No Power
Off
There is no power applied to the module.
Device Operational
Green
The module is operating normally.
Device in Standby
Flashing Green
The module has no configuration.
Minor Fault
Flashing Red
Recoverable Fault
Unrecoverable Fault Red
The module has an unrecoverable fault.
Device Self Testing
Flashing
The module is in Self Test.
Red-Green
Network Status LED (NS)
Network
For this state
Status
Condition
LED is
Not powered or
Off
The module may not be powered.
not On–line
Module is not on–line.
Module has not completed Dup_MAC_ID test.
The module is on–line and has connections in the
Module
On–line Green
established state.
and
connected.
Network OK
Module On–line but Flashing Green Module has passed the Dup_MAC_ID test
not connected
and is on–line, but has no established
connections to other nodes.
Connection
Flashing Red
One or more Connections have Timed–Out.
Time–Out
Critical Link Failure Red
Failed communication device.
Device Self Test
Flashing
Device is in self test
Red-Green
Device in Standby Flashing Red
The module has no configuration
PAGE 12
23 JUN 2000
NOTES
CH. 2: INSTALLATION
CH. 3: DeviceNet Node
23 JUN 2000
PAGE 13
CHAPTER 3: DEVICENET NODE, DNT250 & PLC RELATIONSHIPS
3.1
General
Unless otherwise noted, all numeric radixes are in decimal. In a few cases the notation 0xhh is
used to indicate Hexadecimal radix.
3.2
Module to PLC Register Mapping
The %I, %Q, %AI and %AQ register references within the PLC Rack configuration allow the
starting location of each of these groups of registers to be assigned to specific locations within the
PLC register space.
With respect to the examples in this manual, the PLC Rack register references are set to one.
This simplifies our examples by assuming that the register reference assignments start one. That
is, the first %I, %Q, %AI and %AQ registers are assigned to PLC register %I1, %Q1, %AI1 and
%AQ1. Although these references can be assigned anywhere within the PLC register space, we
have made these assignments for simplicities sake.
3.3
Node to PLC Register Mapping
The DNT250 DeviceNet Scanner also provides mapping between the PLC’s data registers and
each individual DeviceNet node. For each configured node, the DNT250 provides mapping
between the PLC’s %Q, %AQ, %I and %AI registers and the DeviceNet node’s data assembles.
As a result, each nodes polled data is immediately available to the PLC ladder code by accessing
the appropriate PLC register. Note that the Node to PLC register assignments must be contained
within the Module register definitions defined in Module to PLC Register Mapping defined above.
3.4
Message Packets and Fragmentation
A DeviceNet message packet can contain from 0 to 8 bytes of data. If more than 8 bytes of data
are required, the message must be broken up into two or more packets or fragments. This is
called fragmentation. The DNT250 handles this automatically, without any intervention by the
user or the ladder program running in the PLC.
Fragmentation works differently for Polled messages versus Explicit messages. In the case of
Polled messages, each message fragment is sent as fast as possible. In the case of large Explicit
messages, the sender will send only the first packet. The sender then waits for an ACK message
from the receiver. Upon receiving the ACK, the sender then transmits the next packet then waits
for another ACK. This process repeats until all message fragments have been sent. This ACK
process requires a considerable amount of time when compared to Polled fragmentation. As a
result, LIEM or explicit messaging should be limited to data that needs to be accessed
infrequently such as tuning or configuration parameters.
3.5
Physical Limitations
There are physical limits on the amount of data that can be transferred between the DNT250 and
the PLC. This limit is 254 bytes of input data and 254 bytes of output data. The input limit is
computed as the sum of all %I registers, in terms of bytes, plus the number of %AI registers times
2. The output limit is computed as the sum of all %Q registers, in terms of bytes, plus the number
of %AQ registers times 2. Because of this size restriction, the number of data bytes that can
appear on the DeviceNet network is also limited accordingly. This is a physical limitation of the
Series 9030 PLC backplane.
PAGE 14
23 JUN 2000
CH. 3: DeviceNet Node
There are also limits, depending on the PLC model, on the number of %I, %Q, %AI and %AQ
registers supported. Consult the specific PLC model’s documentation for more information.
The smallest data item that DeviceNet can handle is one byte. If an application requires only a
single %Q output or command bit, a group of 8 %Qs must be allocated. The remaining 7 will be
unused (or wasted). The same is true for bit type input data.
3.6
Data Assemblies
For a Polled Connection, the data bytes within the DeviceNet messages must be sent or received
in a predetermined order. This order is specified by “Data Assemblies”. Data Assemblies are
published by the manufacturer of each specific DeviceNet node. To properly map the DeviceNet
data to or from the PLC, the data assemblies for each DeviceNet node must be understood.
Consult data sheets from each DeviceNet node manufacture for specific details.
From the point of view of the PLC, all input is via %I and %AI registers and all output data is via
%Q and %AQ registers. From the point of view of DeviceNet nodes, all I/O is via streams of data
bytes, known as data assemblies, that it sends or receives. In some DeviceNet nodes, the data
assembly formats are fixed, in others they are configurable.
The DNT250 accepts output data from the PLC in the form of %Q and/or %AQ registers. It then
translates this output data into DeviceNet polled messages, and sends them to the addressed
DeviceNet node. The DNT250 then receives DeviceNet polled response messages from the
addressed DeviceNet node, translates these DeviceNet messages and passes the data on to the
PLC where they are stored in the appropriate %I and/or %AI registers.
For the DNT250, it is expected that any bit data will be transmitted first, followed by any word
data. For example, if eight (8) %Q registers and 3 %AQ registers are to be sent, the following
Data Assembly would result:
BYTE
0
1
2
3
4
5
6
FUNCTION
Bit data %Q1 to %Q8
%AQ1 LSB
%AQ1 MSB
%AQ2 LSB
%AQ2 MSB
%AQ3 LSB
%AQ3 MSB
CH. 3: DeviceNet Node
3.7
23 JUN 2000
PAGE 15
DNT250 Configuration Introduction
Configuration of the DNT250 is performed using a PC running the configuration program
DNCFG.EXE. There are a number of steps required in order to properly configure the DNT250
DeviceNet scanner module. These steps include:
Specify the DNT250’s MACID
Specify the network baud rate,
Specify if explicit messaging is to be supported
Specify the module offsets for each of the register types (%Q, %AQ, %I and %AI).
Define the Scan List,
And for each node included in the Scan List:
Specify the %I Reference Address
Specify the %I Size (in Bits)
Specify the %AI Reference Address
Specify the %AI Size (in Words)
Specify the %Q Reference Address
Specify the %Q Size (in Bits)
Specify the %AQ Reference Address
Specify the %AQ Size (in Words)
Specify the Expected Packet Rate for the Polled Connection
Each of these items are discussed below:
Specify the DNT250’s MACID.
This is the network address that the DNT250 will respond to. All nodes on the network,
including the DNT250 must be configured with a unique MACID.
Specify the network baud rate.
This is the data bit rate at which all nodes on the network will operate. All nodes on the
network must be configured to operate with the same baud rate.
Specify if explicit messaging is to be supported.
If the application requires LIEM or explicit messaging to be performed with any network
node, this check box must be marked. This will determine which Data Assemblies are
selected for the DNT250.
Specify the module reference addresses for each of the register types (%Q, %AQ, %I and %AI).
When the PLC Rack configuration is performed the module register addresses (or Base
Addresses) will be required. The module reference addresses specify the start of each
block of registers that are assigned to the DNT250 for each register type.
Scan List.
Before the DNT250 can communicate with any DeviceNet nodes, it must be loaded with
a Scan List. The Scan List specifies which DeviceNet MACIDs to query. Only those
nodes specified in the Scan List are considered to exist on the network.
For each node included in the Scan List:
The DNT250 also needs additional information about each node in the Scan List. This
information includes a Reference Address and Size for each of the PLC register types
(%Q, %AQ, %I and %AI). These items tell the DNT250 where the specific node data is
mapped within the PLCs registers and the size of that data. We also need to know the
Expected Packet Rate for the node. The Expected Packet Rate is in terms of
milliseconds. This value is sent to the node where it is used as an inactivity timeout.
Internal to the node, the value is multiplied by four and is used to measure the time
between accesses by the DeviceNet master. If the node does not receive any messages
from the master within this period of time, the node will enter the timed-out state,
effectively going off-line.
PAGE 16
23 JUN 2000
NOTES
CH. 3: DeviceNet Node
CH. 4: DNT Status
23 JUN 2000
PAGE 17
CHAPTER 4: DNT250 STATUS AND COMMAND DATA ASSEMBLIES
4.1
Register Requirements and Definitions of Data Assemblies
The DNT250 requires several PLC registers to be assigned to itself. The DNT250 actually
provides two different sets of data assemblies. The specific set that is selected is determined by
the Explicit Support bit in the DNT250 module configuration. If Explicit Support is selected, the
DNT250 needs more registers in order to handle the Explicit Messaging. See Appendix B. The
following tables define the DNT250 register requirements and definitions of each of these data
assemblies:
Table 4.1 - DNT250 Register
Requirements
Explicit Support?
No
Yes
Number of %Q’s
8
8
Number of %AQ’s
0
4
Number of %I’s
8
16
Number of %AI’s
4
4
%Q1
%Q2
%Q3
%Q4
%Q5
%Q6
%Q7
%Q8
%AQ1
%AQ2
%AQ3
%AQ4
Table 4.2: DNT250 Output Data Assemblies
Explicit Support = no
Explicit Support = yes
Stop DeviceNet Scanning
Stop DeviceNet Scanning
Not Defined – Reserved
Send Explicit Message
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Defined – Reserved
Not Used (available)
Not Used (available)
Not Used (available)
Not Used (available)
Transmit Buffer %R Number
Transmit Buffer Size (in bytes)
Receive Buffer %R Number
Receive Buffer Size (in bytes)
PAGE 18
%I1
%I2
%I3
%I4
%I5
%I6
%I7
%I8
23 JUN 2000
CH. 4: DNT Status
Table 4.3 - DNT250 Input Data Assemblies
Explicit Support = no
Explicit Support = yes
Someone is Off Line
Someone is Off Line
DeviceNet scanning is stopped
DeviceNet scanning is stopped
Not Defined – Reserved
Explicit Transaction Complete
Not Defined – Reserved
Explicit Error – Buffer Allocation Error
Not Defined – Reserved
Explicit Error – Can't get %R buffer
Not Defined – Reserved
Explicit Error – Invalid MACID
Not Defined – Reserved
Explicit Error – Node not configured
Not Defined – Reserved
Explicit Error – Node not on-line
%I9
%I10
%I11
%I12
%I13
%I14
%I15
%I16
Not Used (available)
Not Used (available)
Not Used (available)
Not Used (available)
Not Used (available)
Not Used (available)
Not Used (available)
Not Used (available)
Explicit Error – Can't make explicit connection
Explicit Error – Operation timed out
Explicit Error – other DNT Error
Explicit Error – Receive buffer overrun
Explicit Error – Can't put %R buffer
UCMM Exp Enable Error
Not Defined – Reserved
Not Defined - Reserved
%AI1
%AI2
%AI3
%AI4
On Line status, nodes 0-15
On Line status, nodes 16-31
On Line status, nodes 32-47
On Line status, nodes 48-64
On Line status, nodes 0-15
On Line status, nodes 16-31
On Line status, nodes 32-47
On Line status, nodes 48-64
%Q1 Stop DeviceNet Scanning
Setting this bit causes the DNT250 to close or release all connections between itself and
all DeviceNet nodes. No further communications will occur between the DNT250 and the
DeviceNet nodes until the Stop DeviceNet Scanning bit is cleared. While the scanning is
stopped, the DeviceNet Scanning is Stopped bit %I2 bit will be set.
%Q2 Send Explicit Message
When this command is issued the DNT250 will attempt a LIEM sequence. The specifics
of the LIEM are discussed in chapter 4. %I3 through %I13 are used to report the
completion status of this command.
%Q3-8 Not Defined - Reserved
These bits are reserved and can not be used for any purpose.
%AQ1 Transmit Buffer First %R Number
For LIEM sequences, this register must be loaded with the number of the first %R
register of the explicit message transmit buffer. See chapter 4 for more details.
%AQ2 Transmit Buffer Size (in Bytes)
For LIEM sequences, this register must be loaded with the number of bytes of data to be
sent to the target node. See chapter 4 for more details.
%AQ3 Receive Buffer First %R Number
For LIEM sequences, this register must be loaded with the number of the first %R
register of the explicit message receive buffer. See chapter 4 for more details.
CH. 4: DNT Status
23 JUN 2000
PAGE 19
%AQ4 Receive Buffer Allocation Size (in Bytes)
For LIEM sequences, this register must be loaded with the size in bytes of the receive
buffer. This value can be as large as the programmer likes, but an error will result if the
node sends a message that is larger than will fit in the receive buffer. See chapter 4 for
more details.
%I1 Someone is Off Line
This status bit indicated that one or more configured nodes are not on line.
%I2 DeviceNet Scanning is Stopped
This status bit indicates that the DeviceNet scanning is stopped as a result of the bit %Q1
Stop DeviceNet Scanning having been set by the PLC.
%I3 Explicit Transaction Complete
This status bit indicates that the requested LIEM sequence is complete. Once this bit is
set, the PLC must check bits %I4 through %I14 which indicate if any errors have
occurred.
%I4 Explicit Error – Buffer Allocation Error
If set, this LIEM status bit indicates that the values in %R1 and %R2 or %R3 and %R4
are in error. The transmit buffer and/or the receive buffer is/are outside the available %R
registers of the specific PLC CPU model.
%I5 Explicit Error – Can’t get %R Buffer
If set, this LIEM status bit indicates that the DNT250 was unable to read the transmit
buffer from the PLC.
%I6 Explicit Error – Invalid MACID
If set, this LIEM status bit indicates that the MACID contained in the transmit buffer is too
large.
%I7 Explicit Error – Node Not Configured
If set, this LIEM status bit indicates that the MACID contained in the transmit buffer is not
configured.
%I8 Explicit Error – Node Not On Line
If set, this LIEM status bit indicates that the MACID contained in the transmit buffer is not
On Line.
%I9 – Explicit Error
Can’t make explicit connection. If set, this bit indicates that the explicit connection can
not be made.
%I10 Explicit Error – Operation Timed Out
If set, this LIEM status bit indicates that the LIEM sequence timed out. Most likely the
target node did not send a response in a timely manner.
%I11 Explicit Error – Other DeviceNet Error
If set, this LIEM status bit indicates that some other miscellaneous DeviceNet error
occurred.
%I12 Explicit Error – Receive Buffer Overrun
If set, this LIEM status bit indicates that the response message received from the target
node was too large to fit in the receive buffer indicated by %R3 and %R4.
%I13 Explicit Error – Can’t put %R Buffer
If set, this LIEM status bit indicates that the DNT250 was unable to write the receive
buffer to the PLC.
PAGE 20
23 JUN 2000
CH. 4: DNT Status
%I14 Explicit Error – UCMM Exp Enable Error
If set, this LIEM status bit indicates that an attempt was made to perform an LIEM to a
UCMM type node without the UCMM Exp Enable bit set.
%I15 Not Defined – Reserved
%I16 Not Defined – Reserved
These bits are reserved and can not be used for any purpose.
%AI1 On Line Status of Nodes 00 - 15
%AI2 On Line Status of Nodes 16 - 31
%AI3 On Line Status of Nodes 32 - 47
%AI4 On Line Status of Nodes 48 - 63
These four %AI registers collectively contain 64 individual status bits. One bit is assigned
to each of the 64 possible DeviceNet node addresses. Status bits for nodes 0 through 15
are mapped into the first %AI register. Status bits for nodes 16 through 31 are mapped
into the second %AI register. Status bits for nodes 32 through 47 are mapped into the
third %AI register. Status bits for nodes 48 through 63 are mapped into the fourth %AI
register. The status bit for node 0 is placed in the least significant bit position of the first
%AI register, with consecutively higher addressed nodes status bits being placed in the
next higher bit positions. See the table below.
Each individual status bit is set TRUE if the corresponding DeviceNet node is On Line.
On-Line is defined as the node’s Polled connection being in the Established state and the
node is communicating Polled data.
Bit
Number
MACID
15
14
Table 4.4 – HE693DNT250 Unit Status Bits
%AI[offset+0]
13 12 11 10 9
8
7
6
5
4
15
14
13
12
11
10
7
6
5
4
3
2
1
0
Bit
Number
MACID
15
14
13
12
11
%AI[offset+1]
10 9
8
7
6
5
4
3
2
1
0
31
30
29
28
27
26
23
22
21
20
19
18
17
16
15
14
13
12
11
%AI[offset+2]
10 9
8
7
6
5
4
3
2
1
0
47
46
45
44
43
42
39
38
37
36
35
34
33
32
6
5
4
3
2
1
0
54
53
52
51
50
49
48
Bit
Number
MACID
Bit
Number
MACID
9
25
41
8
24
40
15
14
13
12
11
%AI[offset+3]
10 9
8
7
63
62
61
60
59
58
57
56
55
3
2
1
0
Note: Many DeviceNet nodes also provide additional diagnostic data within their individual data
assemblies.
CH. 5: Explicit Messaging
23 JUN 2000
PAGE 21
CHAPTER 5: EXPLICIT MESSAGING USING THE DNT250
5.1
General
The DNT250 DeviceNet Scanner, supports both POLLED and EXPLICIT connections.
Explicit Messaging requires a great deal of overhead in both the DNT250 and the PLC. Explicit
Messaging requires access to the PLC's memory using the BackPlane Mail features of the Series
90-30 system. BackPlane Mail requests are handled only once per PLC logic scan. Large
amounts of data will require multiple PLC scans for all of the data to be transferred between the
PLC and the DNT250. If the PLC is also doing a significant amount of processing, requesting an
Explicit Message can impact the DeviceNet Poll Sequence by several tens of milliseconds. As a
result, Explicit Messages should be reserved for access to infrequently needed data, such as
configuration or tuning parameters only.
The LIEM feature requires that the Explicit Support check box be selected when the DNT250
module is configured. The act of doing this selects the proper data assemblies for the DNT250.
The sequence below presents a general description of the process that must be executed to
service an Explicit request.
1. The ladder code builds an explicit request message in a group of %R registers.
2. The ladder code plugs the start of and length of the transmit and receive buffers into four
%AQ registers. The transmit and receive buffers must both be located in the %R register
space of the PLC.
3. The ladder code then sets the “Send Explicit Message” command bit.
4. At the top of the Scan List, the DNT250 checks the “Send Explicit Message” command bit.
5. If the “Send Explicit Message” command bit is set, processing of the explicit request begins.
6. The four %AQ registers are examined and checked for validity.
7. The DNT250 requests the PLC to send the transmit buffer via Backplane mail.
8. The DNT250 then checks the MACID contained in the transmit buffer. Several checks take
place, MACID out-of-range, referenced node not configured and addressed node not On
Line.
9. Then the message is formatted and sent to the addressed node.
10. When the response message is received, a check is made to see if the allocated receive
buffer is large enough to accept the message.
11. Copy the message to the receive buffer via Backplane mail.
12. Set the Explicit Transaction Complete bit.
13. If there were any error detected in any of the previous steps, the process is aborted and the
appropriate error status bit along with the Explicit Transaction Complete bit are set.
See chapter 3 for descriptions of all of the command, status and error bits.
5.2
Explicit Messages and the DNT250
Early versions of the DNT250 did not support the UCMM but some did support explicit messaging
for Group 2 Only type nodes.
The Group 2 Only nodes allow only one explicit messaging format. The UCMM supports three
additional formats for a total of four formats.
For the least amount impact to those users of early DNT250s who are upgrading, the new
DNT250 supports all of these different explicit message formats. First, the new DNT250 supports
the legacy format of the early DNT250s. The new DNT250 also supports the UCMM formats as
well.
PAGE 22
23 JUN 2000
CH. 5: Explicit Messaging
With respect to the UCMM type nodes, as the DNT250 establishes a connection with the UCMM
node, they negotiate which of the four explicit formats are to be used for all future explicit
communications with that specific node. The DNT250 automatically converts format type as
needed to properly communicate with the various UCMM nodes.
To select between the legacy and UCMM formats, there is a PLC Rack configuration parameter
that must be set up. This parameter, “UCMM Explicit Enable” when cleared to FALSE tells the
DNT250 to use the legacy explicit messaging mode to communicate with “Group 2 Only” type
nodes only. The DNT250 can not do explicit messaging to UCMM type nodes in this mode.
When the parameter, “UCMM Explicit Enable” is set to TRUE, the DNT250 can communicate via
explicit messaging to both UCMM and “Group 2 Only” nodes.
5.3
Building Explicit Messages
As mentioned previously, the DNT250 provides two formats for explicit messages. The format
used depends on the PLC Rack Parameter “UCMM Explicit Enable”. When the “UCMM Explicit
Enable” parameter is clear (FALSE), the legacy format is used.
In the following example, let’s assume that the “UCMM Explicit Enable” parameter is clear or
FALSE. We want to read the polled consumption size from the node at MACID 3, we also want to
locate the transmit buffer at %R101, the receive buffer at %R51 and we will also allocate 20 bytes
to the receive buffer.
BYTE
NUMBER
0
1
2
3
4
REGISTER
NUMBER
R101 LSB
R101 MSB
R102 LSB
R102 MSB
R103 LSB
REGISTER
%AQ1
%AQ2
%AQ3
%AQ4
DESCRIPTION
MACID (Node Address)
Service Code (Get Attribute Single)
Class ID (Connection Class)
Instance ID (Polled Connection)
Attribute # (Consumption Size)
DESCRIPTION
Start of Transmit Buffer
Number of Bytes to Transmit
Start of Receive Buffer
Receive Buffer Allocation Size
TRANSMIT
BUFFER DATA
03
14
05
02
07
VALUE
101
5
51
20
Now, we will repeat the same example except lets assume that the “UCMM Explicit Enable”
parameter is set (TRUE):
BYTE
NUMBER
0
1
2
3
4
5
6
REGISTER
NUMBER
R101 LSB
R101 MSB
R102 LSB
R102 MSB
R103 LSB
R103 MSB
R103 LSB
DESCRIPTION
MACID (Node Address)
Service Code (Get Attribute Single)
Class ID (Connection Class)
Instance ID (Polled Connection)
Attribute # (Consumption Size)
TRANSMIT
BUFFER DATA
03
14
05
00
02
00
07
CH. 5: Explicit Messaging
REGISTER
%AQ1
%AQ2
%AQ3
%AQ4
23 JUN 2000
DESCRIPTION
Start of Transmit Buffer
Number of Bytes to Transmit
Start of Receive Buffer
Receive Buffer Allocation Size
PAGE 23
VALUE
101
7
51
20
In the following example, let’s assume that the “UCMM Explicit Enable” parameter is clear or
FALSE. We want to write the polled expected packet rate to the node at MACID 3, we also want
to locate the transmit buffer at %R101, the receive buffer at %R51, we will also allocate 20 bytes
to the receive buffer.
BYTE
NUMBER
REGISTER
NUMBER
DESCRIPTION
0
1
2
3
4
5&6
R101 LSB
R101 MSB
R102 LSB
R102 MSB
R103 LSB
R104
MACID (Node Address)
Service Code (Set Attribute Single)
Class ID (Connection Class)
Instance ID (Polled Connection)
Attribute (Expected Packet Rate)
Data Value
REGISTER
%AQ1
%AQ2
%AQ3
%AQ4
DESCRIPTION
Start of Transmit Buffer
Number of Bytes to Transmit
Start of Receive Buffer
Receive Buffer Allocation Size
TRANSMIT
BUFFER
DATA
03
16
05
02
07
1000
VALUE
101
7
51
20
Now, we will repeat the same example except lets assume that the “UCMM Explicit Enable”
parameter is set (TRUE):
BYTE
NUMBER
0
1
2
3
4
5
6
7
8
REGISTER
NUMBER
R101 LSB
R101 MSB
R102 LSB
R102 MSB
R103 LSB
R103 MSB
R104 LSB
R104 MSB
R105 LSB
REGISTER
%AQ1
%AQ2
%AQ3
%AQ4
DESCRIPTION
MACID (Node Address)
Service Code (Set Attribute Single)
Class ID (Connection Class)
Instance ID (Polled Connection)
Attribute (Expected Packet Rate)
Data Value Low Byte
Data Value High Byte
DESCRIPTION
Start of Transmit Buffer
Number of Bytes to Transmit
Start of Receive Buffer
Receive Buffer Allocation Size
TRANSMIT
BUFFER DATA
03
16
05
00
02
00
07
E8(Hex)
03
VALUE
101
9
51
20
PAGE 24
5.4
23 JUN 2000
CH. 5: Explicit Messaging
How to Interpret Explicit Response Messages
The normal, expected response from an Explicit Message is the Acknowledge Message:
BYTE
EXAMPLE
DESCRIPTION
NUMBER
0
Number of
06
bytes received
1
00
2
MACID
01
3
*Service Code
0x90(Hex)
4
Optional Data
Xx
Optional Data
Xx
Optional Data
Xx
n
Optional Data
Xx
* Previously sent Service Code (0x10) + 0x80
Note: The Most Significant Bit in the Service Code byte is used as a Response Bit indicating that
the command was properly received. [Service Code 0x10 + Response Bit 0x80 = 0x90]. If any
extra data needs to be returned, that data will be placed into subsequent bytes.
5.5
Explicit Message Errors
In the case that an Explicit Message requests a function that can not be performed by the
addressed node, an Explicit Error Message will be returned in the Receive Buffer
An Explicit Error Message takes the following form:
Byte
Number
Description
0
1
2
3
4
5
Number of bytes
received
MACID
Service Code
General Error Code
Additional Error Code
Example
(values in
HEX)
06
00
01
94
xx
xx
Word
Offset
Value
(from
example)
%R1
0006
%R2
0x9401
%R3
xxxx
Like a "normal" response, the Service Code byte has the Most Significant Bit set as the
Response Bit. Therefore, the actual Error Code is 0x14; with the Response Bit set the received
code is 0x94. Error Code is 0x14 (0x94) has a special meaning. This indicates that the addressed
node has detected an error and the two bytes following indicate the specifics to that error. The
next byte indicates the General Error Code. See appendix C for a list of and definitions of General
Error Codes. Some General Error Codes support an Additional Error Code if appropriate to
indicate additional information.
CH. 6: Configuration
23 JUN 2000
PAGE 25
CHAPTER 6: CONFIGURATION
6.1
General
Before the DNT250 can be used, it must first be properly configured. This consists of two steps:
Module Configuration and PLC Rack Configuration.
IMPORTANT: The module configuration must occur prior to configuring the PLC rack.
6.2
DNT250 Module Configuration
Included with the DNT250 module is a diskette containing the configuration utility, DNCFG.EXE.
DNCFG.EXE is a 32 bit Windows application. It can be installed and run on most Windows 95,
Windows 98 or Windows NT based PC. DNCFG.EXE will not run under DOS or Windows 3.1.
The PC must be connected to the DNT250 via the module's integral RS-485 serial port.
Module operational parameters (i.e. MACID, baud rate, Polled Production size, Polled
Consumption size and Expected Packet Rate) are configured on behalf of each node using
DNCFG.EXE. This program also allows entire network configurations to be uploaded or
downloaded to or from the DNT250, saved to or loaded from a disk, or sent to a printer for hard
copy.
Exact details of using the DNCFG.EXE configuration utility can be found in chapter XXX. Before
going there we need to discuss a number of concepts that must be understood before module
configuration can be successfully completed:
1. Does the application require the use of LIEM (explicit messaging)? This will determine which
data assembly must be used for the DNT250 itself.
2. If yes, is LIEM required to address any UCMM type nodes? This will determine if the “UCMM
Exp Enable” bit needs to be set in the rack configuration.
3. At what baud rate does the network need to run? This is needed for the DNT250 module
configuration as well as the configuration of each individual DeviceNet node. All nodes
including the DNT250 must be configured for the same baud rate.
4. Is Data Assembly information available for each DeviceNet node in the network? This can be
in the form of printed information in the manufactures manual or in the form of a EDS file
provided by the manufacture. Note that some EDS files do not provide the nodes’ polled
consumption and production sizes. This information will also be required when the PLC
Ladder Code is written.
5. Assign MACIDs (node addresses) to each DeviceNet node. The MACIDs assigned to each
node it totally arbitrary. The only thing that might have an effect here is the fact that the
DNT250 actually scans the nodes in order by MACID. Gaps can be left in the MACID
assignments to allow for future nodes to be added, if desired. DeviceNet provides for nodes
with lower MACIDs to have a higher network priority. But because of the manner in which the
DNT250 scans the network, this priority advantage does not exist. The MACID for the
DNT250 can be assigned any unused address. Every node on the network must be assigned
a unique MACID.
6. All bit type input data must be assigned to a contiguous block of PLC %I registers and all
word type input data must be assigned to a contiguous block of PLC %AI registers.
7. Furthermore, all bit type output data is required to be assigned to a contiguous block of PLC
%Q registers and all word type output data must be assigned to a contiguous block of PLC
%AQ registers.
PAGE 26
6.3
23 JUN 2000
CH. 6: Configuration
PLC Rack Configuration
Configuration of the GE Series 90-30 Rack can be accomplished via several methods. In this
discussion we will use Logicmaster 90 configuration software. In any case, module configuration
(using DNCFG.EXE) must be completed before the rack configuration should be attempted.
There are four parameters that need to be understood before proceeding with the PLC Rack
configuration. These parameters are:
1. Always 1
This parameter must be set to 1.
2. Block Move
This parameter selects one of two possible methods of moving data to and from the PLC’s
registers.
• When set to 0, data is transferred between the PLC and the DNT250 either one byte or
one word at a time. With this method, there exists the possibility to have a data
consistence problem. It is possible that half of a PLC register could be updated on one
PLC scan and the balance of the same register could be updated on the next PLC scan.
This setting is only provided for compatibility with older versions of the DNT250.
• When set to 1, all data is transferred between the PLC and the DNT250 as one
contiguous uninterrupted block. It is not possible to have any kind of data consistence
problem using this mode. This is the recommended setting for this parameter.
3. UCMM Explicit Enable
This parameter allows selection between the old and new methods of explicit messaging.
Note that the “Explicit Support” check box in the Module configuration must be checked
before this parameter will have any effect.
• When set to 0, the legacy mode of explicit messaging is selected. In this mode, explicit
messaging can only be carried on with Group 2 Only types of nodes. It is not possible to
conduct explicit messaging with UCMM type nodes in this mode. This mode is provided
only for compatibility with older versions of the DNT250.
• When set to 1, explicit messaging can be carried on with both UCMM and Group 2 Only
types on nodes. This mode is suggested for all new system designs.
4. Wait Time
This parameter allows the user to specify the length of time the DNT250 will wait for a
response from a node. Using a zero for this parameter value denotes the use of a default
value of 50 milliseconds. In most applications this value should acceptable. In the case that
there is a node on the DeviceNet that is sluggish in its response, a larger value can be used.
Acceptable values include the series, 10, 20, 30, 40, … 250 milliseconds. The timing
resolution within the DNT250 is 10 milliseconds. Therefore, there is no advantage to use
values that are not divisible by 10. Use caution with smaller numbers, if too small a value is
used, nodes may be logged off line during LIEM explicit messaging.
CH. 6: Configuration
23 JUN 2000
PAGE 27
The following sequence may be used to configure the PLC rack for a DNT250 module via
Logicmaster 90 configuration software:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
Start up the Logicmaster 90 configuration software.
At the Logicmaster 90 software screen select <F2> Configuration Package.
Create a program folder at the prompt (to later store data into) and press <ENTER>.
At the menu screen select <F1> I/O Configuration.
Use arrow keys to select the slot where the DNT250 will reside.
If a scanner configuration already exists in the slot you select, delete the old module by using
the <shift F4> key.
Press <F8> (Other) to select module.
Select Foreign Module by pressing the <F3> key.
Using the information you copied or printed from the DTNCFG.EXE program, fill in values for
the %I reference, %I size, %Q reference, %Q size, %AI reference, %AI size, %AQ reference
and %AQ size parameters.
Set the parameter byte 1 on right side of screen to '1' and press <ENTER>
Set the parameter byte 2, Block Move, on right side of screen to the user selected value and
press <ENTER>
Set the parameter byte 3, UCMM Explicit Enable, on right side of screen to the user selected
value and press <ENTER>
Set the parameter byte 4, Wait Time, on right side of screen to the user selected value and
press <ENTER>
Parameter bytes 5 through 16 should be set to zero.
Exit to main menu by pressing <ESCAPE> key twice.
Download the configuration to the PLC rack by pressing the <F9> key.
Press the <F2> key to save the configuration to the PLC. Press the <ENTER> key to begin
store and overwrite.
Power down the PLC rack.
With the rack power off, plug the DNT250 module into the PLC slot selected during Step 5.
Power up the PLC rack.
If the module ever needs replaced or reconfigured, you must first delete any information appearing
at the selected module's position. If you do not, the new configuration may not be properly
recognized.
6.4
DNT250 Configurator
6.4.1
General
The diskette distributed with the HE693DNT250 module contains the HE693DNT250 DeviceNet
Configuration Utility (DNCFG.EXE) setup program, setup.exe.
1.
2.
3.
4.
Insert the diskette into the A: (or B:) drive.
As always, it is a good practice to make a back-up copy of the installation diskette.
Execute the setup program, setup.exe, on the diskette and follow the instructions for
installation.
The DNCFG.EXE utility program will be installed in the installation directory selected
during setup.
PAGE 28
23 JUN 2000
CH. 6: Configuration
DNCFG.EXE can work off line, with no module attached. Normally, DNCFG.EXE is attached to a
HE693DNT250 module. In order to configure a HE693DNT250 module, the user must first connect
it to the PC:
1.
4.
With the rack power off, plug the HE693DNT250 module into an open I/O slot of
a GE Fanuc Series 90-30 rack.
Plug the SNP adapter (P/N HE693SNP232) into the 15-pin female RS485 port on
the HE693DNT250 module.
Plug one end of the 9-pin female D to 9-pin female “straight-through” cable (P/N
HE693CBLSNP) to the 9-pin end of the SNP Adapter. Connect the free end of
the cable to the desired COM port on the PC. If the PC is equipped with 25-pin COM
ports, use a standard 25-pin female to 9-pin male adapter.
Power up the PLC rack.
6.4.2
Configuration Procedures
2.
3.
The focus of this example configuration is to show how to configure a new network using the
DNCFG.EXE Configuration Utility and creating a Node Template Library. This example shows
one approach of configuring the network, but there are numerous approaches that can be used.
After a network has been created, many of the same procedures can be used to edit the existing
network.
1.
Identify all devices (nodes) that are going to be a part of the network. Although not
mandatory, it is highly recommended that the user first create a template library for all the
nodes on the network. This is helpful if the user intends to use the nodes in other
configurations / applications, because it will decrease re-work. If a template library is not
desired, be sure to refer to Step 1 and 2; Refer to Step 7 for a summary of procedures.
It is also recommended that the user obtain EDS files for each device on the network and
place them into a directory. EDS files contain information that is specific to a device, and
the EDS file can be obtained from the device’s vendor. If an EDS file cannot be obtained,
the user can contact the vendor for the information requested on the General Setup
Screen, which is discussed later in the configuration procedure.
2.
Copy the DNCFG.EXE Configuration Utility from the disk that is sent with the module.
Place the DNCFG.EXE Configuration Utility into a file. Double-click the DNCFG.EXE
Configuration Utility icon in the installation directory.
CH. 6: Configuration
23 JUN 2000
PAGE 29
Note: The title of the screen indicates that the screen is untitled. It remains as such until
the configuration is saved with a unique name.
Figure 6.1 – Untitled Default Configuration Screen
The screen has two window panes. The left pane is the Product Template View, which
is used to store node configuration data in a template library. The user creates the template
library as discussed later in the procedure. Once a template library is created, these templates
can be dragged to the right pane on the screen. The nodes can then be configured.
The right pane is the Network View where the user can build a visual representation of a network
depicting the DNT250 Master and all slave nodes (devices). The nodes are configured in this
view.
3.
Creating a Node Template Library with or without using EDS Files.
Note:
Creating a template for a node is not to be confused with configuring a node.
PAGE 30
23 JUN 2000
CH. 6: Configuration
Creating a Template for a Node using an EDS File
Note: Before importing an EDS file, it is recommended to save any changes already done to the
network and library. A faulty EDS file can possibly cause malfunction in the program when the
file is being “read” by the program. A faulty EDS file refers to one that does not conform to the
DeviceNet standard.
To import EDS files, refer to Figure 6.1 and press Library, Import from EDS File.
The following screen appears. Select the desired EDS file and press Open.
Figure 6.2 – EDS Files
The following screen appears.
Figure 6.3 – Setup Screen in a EDS File (General Tab Selected)
General Tab: This screen is not edited by the user, but it is recommended that the Catalog
Number, Maj. Rev. and Min. Rev. numbers be updated by the user as needed. On the right side
of the screen, a Bitmap icon can be double-clicked by using the left mouse button. Upon doing
so, a bitmap file associated with the node can be selected (if a bitmap has been created) . The
bitmap can be changed by pressing Change Bitmap.
Now, select the DNT250 Tab.
CH. 6: Configuration
23 JUN 2000
PAGE 31
Figure 6.4 – Setup Screen in a EDS File (General Tab Selected)
DNT250 Tab: Each node can have one or more templates associated with it, and the user can
select a desired template using the up-down arrows located next to the Template #. The user
can enter an identifying name in the Template Name block.
The Expected Packet Rate is the time when the master establishes communication with a node.
It sets the timer in the node, and the Expected Packet Rate is used as a basis as a time-out. If
the master does not perform a scan within the Expected Packet Rate x 4, the slave node goes
off-line until the master establishes communication with the node on the next scan.
Note: If EDS files have been used, it is recommended not to modify the Production Size or the
Consumption Size. However, the register sizes can be edited as needed.
To delete the template, press Delete Template. In some instances, a node might need more
than one template. In that case, press Add Template and repeat the template process. To
check each template, the user can use the up-down arrows to select the desire template.
Press OK. Be sure to save the configuration with a unique name.
Creating a Node Template without EDS Files
Right-click anywhere on the screen (see Figure 6.1) and select Add New Node. The following
generic screen appears.
Figure 6.5 – Setup Screen in a EDS File (DNT250 Tab Selected)
PAGE 32
23 JUN 2000
CH. 6: Configuration
General Tab: Although the user does not need to configure this screen, it is extremely useful to
do so. To obtain information about the device including product and vendor codes, it may be
necessary to contact the vendor. On the right side of the screen, a Bitmap icon can be doubleclicked by using the left mouse button. Upon doing so, a bitmap file associated with the node can
be selected (if a bitmap has been created) . The bitmap can be changed by pressing Change
Bitmap.
Now, select the DNT250 Tab: Each node can have one or more templates associated with it,
and the user can select a desired template using the upl-down arrows located next to the
Template #. The user can enter an identifying name in the Template Name block.
The Expected Packet Rate is the time when the master establishes communication with a node.
It sets the timer in the node, and the Expected Packet Rate is used as a basis as a time-out. If
the master does not perform a scan within the Expected Packet Rate x 4, the slave node goes
off-line until the master establishes communication with the node on the next scan.
Specify the %I size, %AI size, %Q size, and %AQ size. Production and Consumption sizes
change automatically to reflect the changes.
To delete the template, press Delete Template. In some instances, a node might need more
than one template. In that case, press Add Template and repeat the process. To check each
template, the user can use the up-down arrows.
Press OK.
4.
Upon pressing OK and saving the template with a unique name (such as Project X), the
following information appears in the Node Template Library on the left pane of the screen.
To create a template for the next node, either select Library, Insert New Item or Import from
EDS File and repeat steps 3 and 4. The user can also right-click on the left pane and select
Insert New Item or Import from EDS File.
Figure 6.6 – Node Information Displayed on Left Pane
5.
After the complete node template library has been created, it is now appropriate to
configure the Network Properties screen (Figure 6.7). Afterwards, the nodes can be placed into
the visual display of the network on the right side of the screen, and then each node can be
individually configured.
CH. 6: Configuration
23 JUN 2000
PAGE 33
Figure 6.7 – Node Information Displayed on Left Pane
Select Network, Properties or double-click anywhere on the screen. A screen similar to Figure
6.7 appears. The user needs to select the scanner type, baudrate, and CPU. The user needs to
set the starting Reference Addresses of the registers. Note that the size of the registers are
based upon the CPU model selected. The size of the registers are not edited by the user, and
they are automatically set by the software. It is important to pay attention to the total Input Bytes
and Output Bytes, and the notes shown on the screen (Figure 6.7) regarding byte limits.
6.
After configuring the Network Properties screen, it is appropriate to place the nodes (one
at a time) into the visual display of the network on the right side of the screen and then configure
the nodes individually.
PAGE 34
23 JUN 2000
CH. 6: Configuration
Left-click on Tmpl-1 and drag and drop it to the right side of the screen (Figure 6.8). The node is
automatically placed into the appropriate position. If other node templates are contained in the
Node Template Library, repeat the drag and drop process.
Drag and drop the
template to the right
side of the screen.
The node is automatically
placed into the appropriate
position.
Figure 6.7 – Left Pane
Figure 6.8 – Node Information Displayed on Left and Right Pane
The node (one master DNT250 or one of 63 possible slaves) can now be configured. Doubleclick Node 1, and the following screen appears in Figure 6.9.
Figure 6.9 – Connection Details Tab (Node 1)
CH. 6: Configuration
23 JUN 2000
PAGE 35
Enter the name and node number. The software program sets the register sizes automatically,
but the user can change the starting reference addresses. After doing so, the user can choose to
press Network, Auto Remap to remap the node in the network.
Caution: Before using the Auto Remap feature, be sure to save the configuration
beforehand. Auto Remap is primarily intended for use in new configurations. Auto
Remap reassigns the reference addresses for all nodes so that no gaps are left in the
map. Auto Remap action can not be undone and needs to be used with caution.
The General Tab [not shown] contains information about the node as shown in Figure 6.3.
7.
If a Node Template Library is not desired, right-click on the right pane and select
Network Properties (if this has not been configured yet). Refer to Step 5 to configure the
Network Properties screen. Then right-click on the right pane again and select Add New Node.
Left-click on the new node and perform the procedures described in Step 3 (to use EDS Files)
and Step 6 to configure the node.
8.
After the network is built, using the mouse, press Network, Select Com Port. Select an
appropriate communication port.
The configuration can now be downloaded from the PC to the DNT250 by selecting Network,
Download. Configuration is now completed.
If a copy of the current configuration is needed, the user can select Network, Upload the
configuration from the DNT250 to the PC.
To verify the current configuration, press the Network, Verify.
Note: While trying to establish communications during upload, download or
verification, an error message may appear. If this happens, try again. If the error persists after
two attempts,
a. Check the module-PC connection
b. Make sure that the Com Port is not in use by another application.
c. Power cycle the PLC.
To document and save information about the node configuration, select
Network, Project Summary.
To see a summary of I/O devices, select Network, I/O Summary.
PAGE 36
23 JUN 2000
NOTES
CH. 6: Configuration
CH. 7: Developing User Software
23 JUN 2000
PAGE 37
CHAPTER 7: DEVELOPING USER SOFTWARE
7.1
Software Support for the Polled Connection
When using the Polled Connection, all inputs from and outputs to the DNT250 are handled by
normal ladder programming techniques to set appropriate values and read any resulting values.
Inputs from the DNT250 (and the DeviceNet nodes) are placed in %I or %AI registers; outputs
are placed into %Q or %AQ registers. Which registers are used is a function of the configuration
of the DNT250 and of the PLC Rack Configuration.
Data is passed via the DeviceNet Polled Connection automatically. Data is read from or written to
the network devices according to the registers programmed using DNCFG.EXE and the LM90
Configurator Program. No extra ladder programming is required to send or receive data using
Polled Messages.
7.2
Software Support for the Explicit Connection
The Explicit Connection requires additional ladder programming support.
The Explicit Connection must first be specifically enabled by marking the EXPLICIT SUPPORT
check box in the DNCFG.EXE configuration program.
During PLC operation, the ladder program must check both the SEND EXPLICIT MESSAGE and
EXPLICIT TRANSMISSION COMPLETE bits. Both bits must be clear. The program must not
modify the %AQ registers nor the %R register buffers pointed to by the %AQ registers if either bit
is set.
NOTE: If the Explicit Support check box is not marked, the EXPLICIT TRANSMISSION
COMPLETE bit is permanently set to '1'.
Finding both bits clear, the ladder program may then proceed to build the transmit buffer in %R
Registers. The ladder program must also modify the %AQ registers to point to the %R transmit
and receive buffers.
%AQ1
%AQ2
%AQ3
%AQ4
Offset of Base %R Register for the Transmit Buffer
Size of the Transmit Buffer, in bytes
Offset of Base %R Register for the Receive Buffer
Size of the Receive Buffer, in bytes
The offset of the %R register holding the first word of the Explicit Transmit Buffer is then placed
into the %AQ1. The SIZE of the buffer IN BYTES is placed in %AQ2.
The PLC ladder program must also define a Explicit Receive Buffer. The offset of the %R register
to hold the first word of the received message is placed in %AQ3. The allocated size of the
receive buffer IN BYTES is place in %AQ4. The PLC ladder code must be sure to allocate
enough buffer space (%R registers) to handle the largest expected incoming message.
The ladder program then sets the SEND EXPLICIT MESSAGE bit. The ladder program must then
monitor the EXPLICIT TRANSMISSION COMPLETE bit. This bit will be set when the command is
complete. Fragmentation if required is handled automatically by the DNT250.
After the EXPLICIT TRANSMISSION COMPLETE bit is set, the ladder program must check the
EXPLICIT ERROR BITS for any possible errors. If any errors exist, they should be processed by
the ladder code. If there are any errors are present, any data in the receive buffer should be
considered invalid. If there are no Explicit Errors, the ladder program can then process any
received message in the receive buffer.
PAGE 38
23 JUN 2000
CH. 7: Developing Software User
Finally, the ladder program must "acknowledge" the completion of the transmission by clearing
the SEND EXPLICIT MESSAGE COMMAND bit. The DNT250 will respond by clearing the
EXPLICIT TRANSMISSION COMPLETE bit.
The HE693DNT250 is now ready for another Explicit Message transmission.
Below is a flow chart for the Send Explicit Message command.
Are "Send Explicit" and
"Explicit Complete" bits
clear ?
NO
YES
Build transmit buffer in %R registers,
setup %AQ registers
Set the "Send Explicit" bit
Is the "Explicit
Complete" bit set
?
NO
YES
Are any Error
bits set?
YES
Process Errors
NO
Process any incoming message
Clear the "Send Explicit" bit.
Is the "Explicit
Complete" bit
clear
NO
DNT250 not responding
properly, if at all.
YES
Done
Handle Error
Figure 7.1 - Explicit Messaging Flow Chart
Appendix A
23 JUN 2000
PAGE 39
APPENDIX A: DNT250 NETWORK OPERATION
1
Sequence of Events
The DNT250 follows a predetermined sequence of events as it attempts to communicate with the
nodes connected to the network. Defined below is this sequence of events:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
2
Starting at the top of the scan list (MACID 1), locate the first node that is configured.
If no nodes are configured, go to step 1.
If this node is On Line, go to step 7.
Attempt to establish a connection with the node. See Establishing a Connection below.
If a connection was successfully established, go to step 7.
If a connection was not successfully established, locate the next node that is configured and
go to step 3.
Read the appropriate %Q and %AQ data from the PLC.
Build a Polled Command message sequence (fragmentation is required if the data size is
greater than 8 bytes).
Sent the message(s) over the network to the node.
Setup a timeout timer.
Wait for the Polled response from the node.
If the timeout expires, take the node offline, locate the next node that is configured and go to
step 3.
Send the response data to the appropriate PLC %I and %AI registers.
Locate the next node that is configured and go to step 3.
Establishing a Connection
There are several steps involved in the establishment of connections with DeviceNet nodes. The
general steps involved include:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
Attempt to establish an Explicit connection using the UCMM protocol.
If unsuccessful, attempt to establish an explicit connection using the Group 2 Only protocol.
If unsuccessful, give up on this node, return
Attempt to establish a Polled connection.
If unsuccessful, release the Explicit connection, give up on this node, and return.
Request the node’s Polled Production size.
If unsuccessful, release the Explicit and Polled connections, give up on this node, and return.
Compare the nodes Polled Production size to the configuration file.
If different, release the Explicit and Polled connections, give up on this node, and return.
Request the node’s Polled Consumption size.
If unsuccessful, release the Explicit and Polled connections, give up on this node, and return.
Compare the nodes Polled Consumption size to the configuration file.
If different, release the Explicit and Polled connections, give up on this node, and return.
Set the nodes Polled Expected Packet Rate.
If unsuccessful, release the Explicit and Polled connections, give up on this node, and return.
Set On Line status for the node and return.
In an effort to minimize adverse effects on nodes that are On Line, the DNT250 will only attempt
to establish a connection with one Off Line node per complete pass through the Scan List.
PAGE 40
23 JUN 2000
Appendix A
Also, every few seconds the DNT250 will send an Explicit message containing a NOP to each On
Line node. The purpose of this is to keep the nodes Explicit connection from timing out. Again,
the DNT250 will only send one NOP message to a single node per complete pass through the
Scan List.
If configured for LIEM (explicit messaging), the DNT250 will at the top of the scan list check to
see if the ladder code is requesting that an explicit message be sent. If so, the explicit request is
processed. This can occur only once per Polled scan.
Appendix B
23 JUN 2000
PAGE 41
APPENDIX B: PACKET TIMING
1
Message Packet Timing
It is not easy to determine the exact transmission time of the DeviceNet Polled scan time. The
table below provides actual timing of single message packets for various baud rates and
message sizes. It must be understood that the table does not take into account the dead time
between the message packets. There are a number of reasons for this dead time, but be assured
that it does exist. The best way to get an accurate handle on the DeviceNet Polled scan time is to
connect a good digital oscilloscope or logic analyzer to the DeviceNet cable while the system is
running.
The amount of data to be transmitted determines the "packet size" and number of packets
necessary. The baud rate determines the amount of time necessary to transmit one packet.
MESSAGE PACKET TRANSMISSION TIMES
Number of Data Bytes in
0
1
2
Message
Number of BITS in
47
55
63
message packet
Transmission time @
376 440 504
125K
Transmission time @
188 220 252
250K
Transmission time @
94
110 126
500K
3
4
5
6
7
8
71
79
87
95
103
111
568
632
696
760
824
888
µS
284
316
348
380
412
444
µS
142
158
174
190
206
222
µS
Given a message of 'X' bytes, it is first necessary to determine if fragmentation is involved, and if
so how many packets will be sent:
If the size of the message ('X') is eight (8) bytes or less, use the time given in Table 8.
If the size ('X') is more than eight bytes, fragmentation is required:
Number of Full Packets = Message Size / 7
Size of additional packet = (remainder of (message size / 7 ) ) + 1
Time for full packets = Time for 8 bytes, taken from table.
Time for additional packet = Taken from table
Time for full message = Total for all Full Packets + Time for Additional Packet.
For example, suppose that a DeviceNet node requires a Poll Command of 27 bytes:
2
Network Scan Time versus PLC Scan Time
The user should not make any assumptions about the relationship between the PLC scan time
and the DeviceNet Polled scan time. They are totally asynchronous to each other.
Any relationship between the PLC scan time and the DeviceNet Polled scan time can be
determined only with a strong knowledge of the program running in the PLC and the DeviceNet
configuration and operation or by conducting extensive testing.
PAGE 42
23 JUN 2000
NOTES
Appendix B
Appendix C
23 JUN 2000
PAGE 43
APPENDIX C: DEVICENET GENERAL ERROR CODES
The following DeviceNet General Error Codes are defined within the DeviceNet specification and
are supported by all DeviceNet nodes.
Table 1 – General Error Codes
Error Code
(in hex)
00 – 01
02
03 – 07
08
09
0A
0B
0C
0D
0E
0F
10
11
12
13
14
15
16
17
18
19
1A – 1E
1F
20
21 – CF
D0 – FF
Name
Reserved
Resource
Unavailable
Reserved
Service Not
Supported
Invalid Attribute
Value
Reserved
Already in
requested mode
Object State
Conflict
Reserved
Attribute Not
Settable
Privilege Violation
Device State
Conflict
Reply Data Too
Large
Reserved
Not Enough Data
Attribute Not
Supported
Too Much Data
Object Does not
Exist
Reserved
No stored attribute
data
store operation
failure
Vendor Specific
error
invalid parameter
Reserved
Object Class and
Service Errors
Description of error
Resource needed for the object to perform the
requested service were not available
The requested service was not implemented or not
defined for this Object Class/Instance
Invalid attribute data detected
The object is already in the requested mode or state
requested by the service
The object can not perform the requested service in
it's current mode or state
A request to modify a non-modifiable attribute was
received
Permission/privilege check failed
The device's current mode or state prohibits the
requested service
The data to be transmitted is large than the allocated
response buffer
The service did not supply enough data to perform the
requested service
the attribute specified in the request is not supported
The serve supplied more data than was expected
The specified object does not exist in the device
The attribute data of the object was not stored prior to
the requested service
The attribute data of this object was not saved by the
object
Reserved by DeviceNet
A vendor-defined error has occurred. See the
Additional Byte for further information
A parameter associated with the service was
determined to be not valid
Vendor-specific Object and Class errors.
PAGE 44
23 JUN 2000
NOTES
APPENDIX C
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