DNET4CHCONV User Manual - Molex Users... · Web viewObject DeviceNet Object Class # of Instances Identity 1 1 Message Router 2 1 DeviceNet 3 1 Connection 5 3 (Explicit Msg., Polled

DNET1CHCONVRevision 1.0

Single-Channel DeviceNet RS-232 Serial GatewayUser’s Manual

SST, a division of Woodhead Canada Limited

SST/Woodhead Connectivity DNET1CHCONV User’s Manual 09/20/23 Revision 1.0

Although every effort has been made to insure the accuracy of this document, all information is subject to change without notice. Woodhead Industries LP assumes no liability for any errors or omissions in this document or for direct, indirect, incidental or consequential damage resulting from the use of this document.

Rev 0.91October 2002

Copyright © 2002 Woodhead Industries

SST, a division of Woodhead Canada Limited50 Northland Road

Waterloo, Ontario, CanadaN2V 1N3

(Phone) 519-725-5136(FAX) 519-725-1515

(Email) [email protected](Web) http://www.mySST.com

DeviceNet is a trademark of the Open DeviceNet Vendor Association (“ODVA”).All other trademarks are property of their respective companies.

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TABLE OF CONTENTS

1. OVERVIEW........................................................................................................................................... 5

1.1 FEATURES........................................................................................................................................... 51.1 TYPICAL APPLICATIONS....................................................................................................................... 61.2 BASIC OPERATION............................................................................................................................... 6

1.1.1 Polled RS232.................................................................................................................................. 71.1.2 Cyclic Input Message...................................................................................................................... 71.1.3 Change-of-State, or C.O.S.............................................................................................................. 71.1.4 Explicit Messages........................................................................................................................... 7

2. QUICK START..................................................................................................................................... 8

2.1 HOW TO INSTALL AND ESTABLISH DEVICENET COMMUNICATIONS.......................................................82.2 DEFAULT SETTINGS............................................................................................................................. 92.3 HOW TO INSTALL A SERIAL NETWORK...............................................................................................102.4 HOW TO READ SERIAL DEVICE DATA FROM THE DNET1CHCONV...................................................102.5 HOW TO WRITE SERIAL OUTPUT DATA TO THE DNET1CHCONV.....................................................11

3. GENERAL SPECIFICATIONS......................................................................................................... 12

4. HARDWARE INSTALLATION AND SET-UP.................................................................................14

4.1 OVERVIEW......................................................................................................................................... 144.2 MOUNTING........................................................................................................................................ 144.3 LED OPERATION............................................................................................................................... 15

4.3.1 DeviceNet LEDs........................................................................................................................... 154.3.2 Serial Port LEDs.......................................................................................................................... 16

4.4 SERIAL PORT CONNECTOR.................................................................................................................164.5 ROTARY SWITCHES............................................................................................................................ 174.6 DEVICENET PHYSICAL LAYER TOPOLOGY..........................................................................................18

4.6.1 Network Termination.................................................................................................................... 184.6.2 DeviceNet Connection Wiring.......................................................................................................19

5. SOFTWARE CONFIGURATION AND SET-UP..............................................................................20

5.1 DEVICE PARAMETERS........................................................................................................................ 205.2 SETTING UP DEVICENET COMMUNICATIONS.......................................................................................23

5.2.1 Setting up the Max Receive Character Buffer Length....................................................................245.2.2 Setting up the Max Transmit Character Buffer Length..................................................................245.2.3 Setting up and Using Pad Mode....................................................................................................245.2.4 Byte Swap Mode........................................................................................................................... 255.2.5 Setting Up the Scanners I/O Sizes.................................................................................................255.2.6 Setting up the DeviceNet I/O Connections.....................................................................................265.2.7 Setting up the DeviceNet Baudrate...............................................................................................27

5.3 SETTING UP THE SERIAL LINK............................................................................................................ 275.3.1 Reception Overview...................................................................................................................... 275.3.2 Transmission Overview................................................................................................................. 275.3.3 Physical Layer Properties.............................................................................................................285.3.4 Hardware Handshaking................................................................................................................ 285.3.5 The Receive Delimiter.................................................................................................................. 285.3.6 The Transmit Delimiter................................................................................................................. 295.3.7 Status Byte Description................................................................................................................. 29

6. ASSEMBLY OBJECT FORMATS....................................................................................................30

6.1 ASSEMBLIES...................................................................................................................................... 30

A. THEORY OF OPERATION.............................................................................................................. 31

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A.1 THE TRANSMIT RECORD ALGORITHM.................................................................................................31A.1.1 Basic Theory of operation......................................................................................................... 31

A.2 THE RECEIVE RECORD ALGORITHM...................................................................................................31A.2.1 Basic Theory of operation......................................................................................................... 31

B. DEVICENET PROFILE, OBJECTS AND SERVICES.....................................................................34

B.1 DNET1CHCONV DEVICENET PROFILE.............................................................................................34B.2 ASSEMBLY OBJECT FORMATS.............................................................................................................35B.3 IDENTITY OBJECT, CLASS 1................................................................................................................ 36B.4 PARAMETER OBJECT, CLASS FHEX (15DEC)..........................................................................................37B.5 SERIAL PORT OBJECT (0X70)............................................................................................................. 38B.6 TRANSMIT RECORD OBJECT, CLASS 113 (0X71).................................................................................38B.7 RECEIVE RECORD OBJECT, CLASS 114 (0X72)....................................................................................41B.8 Common DeviceNet Services............................................................................................................ 43

TABLE OF FIGURESFIGURE 1-1 DNET1CHCONV......................................................................................................................... 5FIGURE 4-1 DNET1CHCONV MOUNTING AND PHYSICAL LAYOUT................................................................15FIGURE 4-2 RS232 DB9 CONNECTOR PIN-OUT...............................................................................................17FIGURE 4-3 DEVICENET CONNECTOR – MICRO, MALE.....................................................................................19FIGURE A-1 TRANSMIT RECORD ALGORITHM FUNCTIONAL FLOWCHART.........................................................31Figure A-2 Receive Record Algorithm Functional Flowchart........................................................................32

LIST OF TABLES

TABLE 1-1 RS232 MESSAGE TYPES.................................................................................................................. 7TABLE 2-1 DEFAULT INPUT (SERIAL RECEIVE) ASSEMBLY FORMAT................................................................11TABLE 2-2 DEFAULT OUTPUT (SERIAL TRANSMIT) ASSEMBLY FORMAT..........................................................11TABLE 4-1 MODULE STATUS LED (LABELED MS)..........................................................................................15TABLE 4-2 NETWORK STATUS LED (LABELED NS).........................................................................................16TABLE 4-3 RS232 CONNECTOR SIGNALS........................................................................................................16TABLE 4-4 BAUD RATE SWITCH (BAUD).......................................................................................................17TABLE 4-5 DEVICENET ADDRESS SWITCHES...................................................................................................17TABLE 4-6 MAXIMUM NETWORK CABLE LENGTHS.........................................................................................18TABLE 4-7 DEVICENET CONNECTOR PIN-OUT.................................................................................................20TABLE 5-1 CONFIGURATION PARAMETER LIST................................................................................................21TABLE 5-2 SERIAL STATUS BYTE................................................................................................................... 29TABLE 6-1 CONSUME ASSEMBLY.................................................................................................................... 30TABLE 6-2 PRODUCE ASSEMBLY.................................................................................................................... 30TABLE B-1 DEVICENET OBJECTS.................................................................................................................... 34TABLE B-2 POLL PRODUCE DATA (ASCII RECEIVE STRING)...........................................................................35TABLE B-3 I/O CONSUME ASSEMBLY FORMAT (ASCII TRANSMIT STRING).....................................................35TABLE B-4 IDENTITY OBJECT CLASS ATTRIBUTES (INSTANCE 0).....................................................................36TABLE B-5 IDENTITY OBJECT INSTANCE ATTRIBUTES (INSTANCE 1)................................................................36TABLE B-6 IDENTITY OBJECT COMMON SERVICES..........................................................................................36TABLE B-7 PARAMETER CLASS ATTRIBUTES (INSTANCE 0).............................................................................37TABLE B-8 PARAMETER INSTANCE ATTRIBUTES (INSTANCES 1-7)...................................................................37TABLE B-9 PARAMETER COMMON SERVICES..................................................................................................37TABLE B-10 SERIAL PORT OBJECT INSTANCE ATTRIBUTES..............................................................................38TABLE B-11 TRANSMIT RECORD OBJECT INSTANCE ATTRIBUTES....................................................................39Table B-12 Receive Record Object Instance Attributes.................................................................................41

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1. Overview The DNET1CHCONV is a DeviceNet-to-serial link communications gateway that provides a flexible DeviceNet interface to an RS232/ASCII device. A wide variety of serial RS232 devices can be easily connected as DeviceNet slaves.

The DNET1CHCONV does not interpret the data being transmitted across it, and so the transferred messages may contain data of any nature or definition. This allows you to use the same gateway for many different DeviceNet-serial interface applications.

Using the DNET1CHCONV you may communicate with the connected peripheral devices in the same fashion as the other DeviceNet devices in the system. Data may be read/written using either RS232 or explicit messaging. Typically real-time data is read and written by the RS232 connection by DeviceNet via Polled, Change-of-State or Cyclic implicit messaging and parameters are read and written with the explicit messaging technique. However, you may also read and write serial data via explicit messages.

The DNET1CHCONV is defined as a Communications Adapter device on the DeviceNet system. It has a 9-pin D-sub connector for connection to the RS232 interface port on your device and one 5-pin “micro” connector for connections to the DeviceNet network. The DNET1CHCONV has one assigned DeviceNet address, which is set by two 10-position rotary switches on the unit. There is also one rotary switch for the DeviceNet baud rate. Other DNET1CHCONV parameters are software-configurable. Each DNET1CHCONV has 2 standard green/red DeviceNet LED’s for module status and network status and two green LED’s for the serial port to indicate RS232 transmit and receive activity.

Figure 1-1 DNET1CHCONV

1.1 FeaturesThe DNET1CHCONV has the following features:

Translates messages and data between DeviceNet and a serial peripheral device

DNET Group 2 Only Slave

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Conformance tested to DeviceNet Spec 2.0; Errata 5.

Defined as a DeviceNet Communications Adapter Device Profile 12 (Chex)

Autobaud operation

Supports ADR functions

Messaging of Serial Data (Poll or Change of state configurations)

Explicit Messaging for Serial Configuration and data.

Pad mode allows fixed DeviceNet size with variable-length receive strings

Byte swapping option

Software Configurable Parameters for serial port operation

Address selection via rotary BCD switches

Panel mount with stand-offs or encased with screw mounts

1 male Micro DeviceNet connector

1 male DB9 RS-232 Connector

Standard DeviceNet module and network status LED’s

2 serial transmit and receive LED’s

Powered from DeviceNet 11-25 Vdc network power

RS232 string length up to 128 bytes

Serial port baud rate up to 115.2k baud

Serial port supports RTS/CTS hardware handshaking option

1.1 Typical Applications Weigh scales

Bar code readers and scanners

Display panels

Robots

Drives

Motion controllers

Operator stations / HMI

Magnetic code readers

1.2 Basic Operation The DNET1CHCONV operates as the DeviceNet front-end to the serial device(s). This DeviceNet “slave” can receive and send data to and from the DNET1CHCONV via the methods described in this section. It sends the data to the device and likewise accepts responses from the device, which are passed back to the DeviceNet system as required.

The DNET1CHCONV has one DeviceNet address. All DeviceNet messages to the DNET1CHCONV are sent to this address. DeviceNet messages to and from the serial device can be sent to the DNET1CHCONV DeviceNet assembly objects using explicit messaging

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commands.

The DNET1CHCONV Parameter Object allows you to define the specific operation of each DNET1CHCONV. These parameters include all the set-up required for the serial communications link.

The following chart and section defines the various messaging methods used for “typical” data types at your serial device and a brief explanation follows.

Table 1-1 Implicit Message Types

Typical Data Polled Cyclic Bit-Strobe

Change-of-State RS232

Commands Ö Ö Ö Ö

Status Ö Ö Ö Ö

Parameters Ö

1.1.1 Polled MessageThe device uses the DNET1CHCONV’s predefined polled connection to send serial input and output data to the DNET1CHCONV. When a poll is received and the record has changed since the last poll was sent, the DNET1CHCONV sends the associated transmit data out the serial port to the remote device. When the DNET1CHCONV receives serial data from a device on the serial link, the poll response data to the polling command contains up to 50 bytes of received data.

1.1.2 Cyclic Input Message Cyclic messaging is the function by which a slave device sends its input data to the master at a specific time period without the host explicitly requesting it. When the specified time interval (defined by you) elapses, the most recent input data from the serial port are transmitted to the RS232. This data is the same format as a poll response.

1.1.3 Change-of-State, or C.O.S. COS messaging is the function by which a slave device sends its input data to the device when defined input data changes without the host explicitly requesting it. In the case of the DNET1CHCONV, this occurs when the delimiter character is asynchronously received from the serial device, when the defined number of characters is received or when the internal buffer is filled. This data is the same format as a poll response.

1.1.4 Explicit MessagesExplicit messages are typically used to read and write configuration data. This data allows the DNET1CHCONV to change its internal operating parameters such as its baud rate and parity. In addition, the user can use explicit messages to read and write the serial port data.

2. Quick Start To quickly install your DNET1CHCONV in your DeviceNet system, follow the instructions below. For more details, see Section 4.

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2.1 How to Install and Establish DeviceNet Communications1. Connect your DeviceNet network cable to a 5-pin female (e.g. Brad Harrison DND22NB-

M0X0 or DND32NB-M0X0) micro-style connector according to DeviceNet cable wiring specifications. Connect the serial device to the gateway using a null cable. Load the EDS file (download from www.mysst.com) into the network configuration manager.

2. Make sure that the DeviceNet network is properly terminated.

3. The DNET1CHCONV Node Address (MacID) is set to 63 at the factory. Make sure no other device on the network is set to 63, or change the DNET1CHCONV address to one that is not currently used (see below).

4. The DNET1CHCONV baud rate is set to Autobaud operation at the factory. No baud rate setting is required.

5. Make sure that there is power on the DeviceNet network and plug the cable into the DNET1CHCONV. Make sure that the configuration manager loads the proper EDS file given the node address assigned to the serial gateway.

6. The DNET1CHCONV will undergo its initialization sequence, flashing both LED’s red and green. After approximately 5 seconds, the Module Status LED (labeled “MS”) will flash green. The Network Status LED (labeled “NS”) will remain off. This condition occurs while the DNET1CHCONV is attempting to synchronize to the network baud rate.

7. The Module Status LED (“MS”) will go on solid after the Device successfully determines the network baud rate. This requires devices on the network attempting to communicate with each other. The Network Status LED (labeled “NS”) will begin to flash green. If it turns solid red, check for a duplicate MacID on the network. It will remain off until the DNET1CHCONV receives a valid DeviceNet message from which it will set its baud rate.

8. The NS LED will now be blinking green. Configure your scanner to talk with the unit at the baud rate and address that you have defined.

9. Once the master recognizes the unit on the link and allocates the connection (initiates communications), the network status LED will be solid green. The device is now being actively scanned.

10. The DNET1CHCONV is now operating on the network.

2.2 Default SettingsThe following list shows the default set-up for all the parameters.

Serial Port Default Operation

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Serial Character Framing 8N1

Serial Port Comm Speed 9600 baud

RTS/CTS Handshaking Disabled

Serial Port Receive from RS232 Device Default Operation

Max Number of Receive Chars 20

Receive End Delimiter Carriage return

Gateway Send (Produce) on DeviceNet to RS232 Default Operation

Pad Mode ON

Pad Character null character (0)

Receive Swap Mode Off

Gateway Produce Assembly Size 24 bytes

Serial Data --

Actual Received Data Size 0

Receive Record Number 0

Serial Port Transmit to RS232 Device Default Operation

Max Number of Transmit Chars 20

Transmit End Delimiter Character Carriage return

Transmit Swap Mode Off

Gateway Consume Assembly Size 24 bytes

Actual Serial Data String to Send to RS232 Device --

Transmit Serial Data Size 0

Transmit Record Number 0

for details on all parameter options.)

2.3 How to Install a Serial Network1. The communication between your serial device(s) and the DNET1CHCONV is an RS232 3-

wire network. Connect an appropriate cable to your serial device.

2. Connect the other end of the cable to the DNET1CHCONV using the 9-pin male DB9 connector. See Section 4.4.

3. Turn on power to the serial device and the DNET1CHCONV.

4. Set up the RS232 buffer sizes on the DNET1CHCONV. (The defaults are 20 and 20). If more than 20 bytes are required for transmit or receive buffers, set the appropriate parameters in your configuration file.

NOTE: This will modify the RS232 message size. You will need to reconfigure the poll / C.O.S. / cyclic transmit and receive data sizes if you modify the RS232 buffer size from the default value. In many configuration tools, this will un-map the data in your scanner’s scan table. They must be remapped in order to be able to process the data in your RS232 or PC

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software. These values are displayed in the Parameter Object, Class 15 (Fhex).

2.4 How to Read Serial Device Data from the DNET1CHCONV1. Set up the device that you want to connect to the network (serial RS-232 connection) per the

manufacturer’s specifications.

2. Connect the serial side of the DNET1CHCONV to your computer’s serial port or another serial device.

3. Go to the device configuration screen in the SST (or other) Configuration Manager.

4. Set the baud rate and framing format of the serial port to the baud rate and framing format of the serial device that you are using.

5. Put the Configuration tool in to monitor mode.

6. Direct the device that you are communicating with to send data. For example, if you are connected to a computer terminal program, type a message into the terminal. When you hit enter, the module will update the data with the message that you typed, and change the Receive Transaction ID.

7. Poll messages work in the same manner as the parameter object interface. The default assembly format of the poll message is shown below.

Table 2-2 Default Input (Serial Receive) Assembly Format

Byte 1 Byte 2 Byte 3 Byte 4 Byte 5-24

0 (reserved) Receive Transaction ID Status Received Data

Length RS232 Data

2.5 How to Write Serial Output Data to the DNET1CHCONV1. Do steps 1-6 of Section above.

2. Enter the serial data that you wish to send in the transmit data parameter.

3. Change the length field to reflect the number of bytes you wish to send.

4. Change the Transmit Transaction ID.

5. The DNET1CHCONV will generate the characters that you typed in on the computer screen.

6. Poll message works in the same manner as the parameter object interface. The assembly formats of these messages are configurable and are covered in Section 6.

Table 2-3 Default Output (Serial Transmit) Assembly Format

Byte 1 Byte 2 Byte 3 Byte 4 Bytes 5-24

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0 (reserved) 0 (reserved)Transmit

Transaction ID

Transmit Data Length RS232 Data

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3. General Specifications Product: DNET1CHCONV Device-Serial Gateway

Description: Communications gateway between a serial capable device over an RS232 interface and a DeviceNet network.

Device Type: Communications Adapter, 12 (0C hex)

Device Profile: Identity Object

Message Router Object

DeviceNet Object

Connection Object

Parameter Object

Serial RS232 Object (vendor-specific)

Transmit Serial Object (vendor-specific)

Receive Serial Object (vendor-specific)

Product Revision: 1.004

Product Code: 102

Vendor ID: 8

DeviceNet Conformance: Designed to conform to the DeviceNet Specification Volume I and II, Version 2.0 Errata 5.

DeviceNet Communications: Predefined RS232/Slave Connection Set, Group 2 Only Server

DeviceNet: Baud rate selection:125k, 250k and 500k baud, and autobaud – switch selectable

Address selection:Address number 0 to 63 – switch selectable (default = 63)Cable Connection:DNET1CHCONV: 5-contact standard DeviceNet male micro connector.

DeviceNet Cable: 5-contact standard DeviceNet micro connectors Woodhead / Brad-Harrison part numbers (DND22NB-M0X0,

DND32NB-M0X0 sold separately)Status Indicators:Module Status: green/red bi-color LED

Network Status: green/red bi-color LED

Serial port: Baud rate: 1200, 2400, 4800, 9600, 19.2k, 38.4k, 57.6k, 115.2k baud (software selectable)

Parity: Odd/even/none (software selectable)

Data bits: 7 or 8 (software selectable)

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Serial port connection: DNET1CHCONV: DB9-M (male, 9-pin D-sub)Use cross-over connection for the connection

Status Indicators:

Transmit Active: green LED

Receive Active: green LED

Network Isolation: 500V

Max Power: 3.75 watts: 340 mA @ 11 Vdc – 150 mA @ 25 Vdc unregulated power supply

Mounting: RS232 rail mount, EN 50022

Size: Length: 6.00” (152,4 mm)

Width: 4.00” (101,6 mm)

Height: 2.08” (52,7 mm)

Operating Temp: 0-60 ºC

Humidity: 0-95% RH, non-condensing

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4. Hardware Installation and Set-Up4.1 Overview

The DNET1CHCONV contains two LED’s to indicate the status of the device and the status of the network. The device is connected to DeviceNet via a standard 5-pin male micro-style connector. It also has two green LED’s to indicate the presence of activity on the RS-232 transmit and receive lines, which is a DB9 male connector. You can use (3) rotary switches to select DeviceNet address and baud rate.

All power for the DNET1CHCONV is derived from the DeviceNet power.

4.2 Mounting

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Figure 4-2 DNET1CHCONV Mounting and Physical Layout

4.3 LED Operation

4.3.1 DeviceNet LEDsThe DNET1CHCONV has two LEDs that provide visual status information to the user about the product and the DeviceNet network. See Table 4-4 and Table 4-5 that follow below for how to interpret LED status indications.

Table 4-4 Module Status LED (labeled MS)

LED State Module Status Meaning

OFF No Power There is no power through DeviceNet.

Green Device Operational DNET1CHCONV is operating normally.

Flashing Green Device in Standby DNET1CHCONV needs commissioning (e.g. attempting autobaud).

Flashing Red Minor Fault Recoverable fault.

Red Unrecoverable Fault DNET1CHCONV may need replaced.

Flashing Red/Green Device Self-Testing DNET1CHCONV is in self-test mode.

Table 4-5 Network Status LED (labeled NS)

LED State Network Status Meaning

OFF No Power / Not on-line DNET1CHCONV has no power or has not completed the Duplicate Media Access Control Identifier Algorithm (Dup. MAC ID Check).

Flashing Green On-line, not connected DNET1CHCONV is on-line but is not allocated to a RS232.

Green On-line DNET1CHCONV is operating normally.

Flashing Red Connection time-out One or more RS232 connections are timed out.

Red Critical link failure DNET1CHCONV has detected an error that makes it incapable of communicating on the link. (Bus-off or Duplicate MAC ID Detected).

4.3.2 Serial Port LEDsThe DNET1CHCONV also has two (2) RS-232 activity LEDs: one for transmit (TX) and one for receive (RX). These LEDs are electrically tied to the serial data lines. The LEDs will flash when there are data signals active on the respective data lines and the DNET1CHCONV is powered.

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4.4 Serial Port ConnectorThe RS232 devices are connected to the DNET1CHCONV via a 3-wire communications cable to a DB9 male connector, or 5 wires if you use RTS/CTS hardware handshaking. See your RS232 device’s User Manual for details on the proper connections.

The RX and TX designators below are referenced with respect to the DNET1CHCONV.

Table 4-6 RS232 Connector Signals

DB9 Pin # RS232 Designator RS232 Signal

2 TX Transmit

3 RX Receive

5 GND Ground

7 RTS Request to Send

8 CTS Clear to Send

Figure 4-3 RS232 DB9 Connector Pin-out

Note: The maximum distance of a RS232 link is 50 feet (15m).

4.5 Rotary SwitchesThere are (2) 10-position rotary switches for device address (MacID) and (1) 10-position rotary switch for DeviceNet baud rate.

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Table 4-7 Baud Rate Switch (BAUD)

Position Definition

0 125k baud

1 250k baud

2 500k baud

3-9 Autobaud

Table 4-8 DeviceNet Address Switches

MSB Position

LSB Position Address

0 0 0

0 1 1

• • •

6 3 63

6 ≥4 Software Selectable

≥7 X Software Selectable

The Software Selectable option of the MacID allows a configuration tool or scanner to change the MacID of the DNET1CHCONV over the DeviceNet network. The Out-Of-box default for the software selectable option is 63. In order to use AAR (The address change component of Automatic Device Recovery) out of the box, you must change the switches to the software selectable range. If the device was powered previously at a different MacID, you may follow these steps to use AAR:

1. Set the switches to MacID 63

2. Power the unit so that it completes the Self Test Sequence

3. Remove the unit’s power after the Self Test Sequence is complete

4. Change the switches to the Software Selectable Range.

5. Re-Apply power.

The unit will now come online as software selectable with an address of 63. This will allow the system to execute the AAR protocol.

Remember that switch selectable devices can still take advantage of ADR. In order to take advantage of ADR in a switch selectable mode, follow these steps:

1. Remove the faulty device

2. Set the switches of the replacement device to the same settings as the switches on the old device.

3. Connect the new device to the network and IO.

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The device will come online at the same MacID and baud rate as the old device. A scanner supporting ADR will then download the stored configuration to the device and resume normal operation.

4.6 DeviceNet Physical Layer TopologyDeviceNet specifications provide for a maximum network distances for the main trunk line and drop lines, depending upon the baud rate used on the network.

Table 4-9 Maximum Network Cable Lengths

Trunk Line Length Drop Length

Maximum Distance Maximum Cumulative

Baud Rate Meters Feet Meters Feet Meters Feet

125k baud 500 m 1640 ft 6 m 20 ft 156 m 512 ft.

250k baud 250 m 820 ft 6 m 20 ft 78 m 256 ft.

500k baud 100 m 328 ft 6 m 20 ft 39 m 128 ft.

4.6.1 Network TerminationA DeviceNet system must be terminated at each end of the trunk line. The host controller and the last DNET1CHCONV or other DeviceNet device on the network must always be terminated to eliminate reflections, even if only two nodes are present. The DeviceNet specifications for the terminating resistor are:

121 ohm

1% metal film

1/4 Watt

An appropriate terminating resistor, Brad Harrison part number such as Brad Harrison DND100/150 for m12 style of connectors and DN100/150 for MINI style of connectors.

IMPORTANT: Per the DeviceNet spec -- do not terminate devices on drop lines.

NOTE: If you are having DeviceNet communications errors, check your network terminations.

With power removed from the network, measure the dc resistance with an ohmmeter. It should measure 60Ω. If it measures 121Ω, add another 121Ω terminating resistor. If it measures ~40Ω, then you have 3 terminators and must remove one. If it measures ~30Ω you have 4 terminators and must remove two.

4.6.2 DeviceNet Connection WiringThe DNET1CHCONV uses a 5-pin standard micro-style DeviceNet connector with male pins.

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Figure 4-4 DeviceNet Connector – micro, male

Table 4-10 DeviceNet Connector Pin-out

Position Definition

1 Drain

2 V+

3 V-

4 CAN_H

5 CAN_L

5. SOFTWARE Configuration and Set-Up

The DNET1CHCONV is an easy device to set up and configure. Using features like the EDS sheets for configuration can expedite the process if you use a network configuration tool that supports them. They provide a graphical interface to the device’s parameters and allow the addition of helpful text descriptions in setting up your device. The current EDS file is available on our websites, www.mysst.com or www.connector.com. If your configuration tool does not support the EDS device profiles, the set up of a DeviceNet device requires a little more understanding of DeviceNet and its operation. This section is designed to fully describe the features of the DNET1CHCONV and to help you set them up. .

The Parameters are defined in this section.

5.1 Device Parameters The DNET1CHCONV is configured using the Parameter Object, Class 15 (0Fhex) as defined in .

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Table 5-11 Configuration Parameter List

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Parameter Param. Instance Access Description Parameter Choices Default

SettingDefault Value

Data Type

Serial Port Parameters

Serial Character Framing 1 Get/Set

Defines the number of data bits, parity in data character

stop bit frames

0 = 7N21 = 7E12 = 7O13 = 8N14 = 8N2

5 = 8E16 = 8O17 = 7E28 = 7O2

8N1 0 USINT

Serial Port Comm Speed 2 Get/Set Defines the baud rate of the

serial port

0 =96001 = 12002 = 24003 = 4800

4 = 19.2k5 = 38.4k6 = 57.6k7 = 115.2k

9600 baud 0 USINT

Serial Port Receive from ASCII Device

Max Number of Receive Chars 3 Get/Set

Maximum number of characters the

DNET1CHCONV expects to receive into its ASCII

port from the serial device

1 – 128 20 chars 20 USINT

Receive End Delimiter 4 Get/Set

Character that identifies the end of the data string from

the ASCII device.

Any valid standard ASCII character

(0 – 127, 0-255)

Carriage return Dhex USINT

Gateway Send (Produce) on DeviceNet to Master

Pad Mode 5 Get/Set

Indicates whether to pad the invalid data region after the delimiter with the pad

character, or to use variable length ASCII responses

0 = Pad Mode Disabled1= Pad Mode Enabled

Enabled 1 USINT

Produce Pad Character 6 Get/Set

The value to use to pad the invalid data portion of the

poll response


(0 – 127 with 7-bit data, 0-255 with 8-bit data)

NULL 0 USINT

Produce Swap Mode 7 Get/Set

If enabled, the position of the bytes in the serial

messages will be swapped every 2, 3 or 4 bytes.

0 = Disabled1 = 16-bit Swap Enabled2 = 24-bit Swap Enabled3 = 32-bit Swap Enabled

Disabled 0 USINT

Gateway Produce

Assembly Size8 Get

Total number of bytes of I/O data that are sent to the

Master from the DNET1CHCONV.

This should be the RX size of your Scanner.

0-132

20 bytes of ASCII data

and 4 header bytes

24 USINT

Received Serial Data 9 Get Serial data in the receive

buffer Any data string Empty SHORT_STRING

Received Data Size 10 Get

Actual number of characters received into the

serial port buffer. 0-128 0 0 USINT

Receive Transaction ID 11 Get/Set

The Produce Record Number to send to the

master 0-255 0 0 USINT

Serial Port Transmit to ASCII Device

Max Number of Transmit Chars 12 Get/Set

Maximum number of characters the

DNET1CHCONV expects to transmit out its serial port to the serial device

1-128 20 chars 14hex USINT

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Transmit End Delimiter Character

13 Get/Set

Character which identifies the end of the transmit data string from DeviceNet to

the ASCII device when the length is specified as 0


(0 – 127 with 7-bit data, 0-255 with 8-bit data)


Consume Swap Mode 14 Get/Set


messages will be swapped every 2 or 4 bytes.


Disabled 0 USINT

Consume Assembly Size 15 Get

Total number of byte of I/O data that are received from

the Master.

This should be the TX size of your Scanner.

0-132

20 bytes of array data

and 4 header bytes

24 USINT

Serial Port Transmit / Explicit Messages from EDS Editor

Transmit Serial Data String 16 Get/Set Serial data to be sent to the

serial transmit buffer ASCII Block Data Empty SHORT_STRING

Transmit Serial Data Length 17 Get/Set Length Of the Transmit

Serial Data 0-128 0 0 USINT

Transmit Transaction ID 18 Get/Set The ID of the current

transmit data buffer 0-255 0 0 USINT

General Information

Status 19 Get

The Combined status byte for the Serial Port Object,

The Receive Record object and the Transmit Record

object.

Bit 0 – TX FIFO OverflowBit 1 – Rx FIFO OverflowBit 2 – Rx Parity ErrorBit 3 – Data in Tx BufferBit 4 – Data in Rx Buffer

No Error Status 0 USINT

Hardware Handshaking 20 Get/Set

Activates / deactivates RTS/CTS hardware

handshaking0 = Not enabled1 = Enabled

Not enabled 0 USINT

5.2 Setting up DeviceNet CommunicationsIn order to set up device net communications, you will need to establish the Transmit Buffer Length and the Receive Buffer Length. These parameters are used to determine the Gateway Consume Size and the Gateway Produce Size. The consume and produce sizes are the TX and RX sizes of your scanner. Additionally, you should consider the use of Pad Mode. Many PLCs require pad mode to be enabled for proper operation of an I/O connection.

The IO Assembly Objects are used to determine where you should send the data. The Buffer Lengths should be long enough to process your message. You may wish to enable Byte Swapping if your PLC aligns data on 16, 24 or 32 bit boundaries. This will allow you to view the data in your file in human readable form.

In the explicit mode of communication, there are several places where you could send your data. For one message transmission and reception, you can talk directly to the IO Assembly Object. For more control, you may talk to the Transmit Transaction Object and the Receive Transaction Object. The IO Assembly objects are described in section 6. The other objects are discussed in Appendix A.

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5.2.1 Setting up the Max Receive Character Buffer LengthThe receive character buffer length is the number of characters that the DNET1CHCONV can receive from your I/O device into its buffer at one time. The length of the data string sent to the DeviceNet Master is less than or equal to this size, plus the header information.

If the DNET1CHCONV receives more characters that this number, it will internally generate an overflow and force the data in the DNET1CHCONV DeviceNet transmit buffer to be sent to the Master. The subsequent received characters will then be received into the buffer and handled as the start of next incoming message string. The overflow bit in the status byte will be set on this event.

Caution: Incoming characters could be missed in the process of handling a string longer than the defined max length.

5.2.2 Setting up the Max Transmit Character Buffer Length The Transmit character buffer length is the number of characters that the DNET1CHCONV can receive in its transmit buffer from the DeviceNet system. This size contributes to the I/O Consume Size. This size can be found in the Parameter object.

If the DNET1CHCONV receives more than this number of bytes in a consumed DeviceNet message from the Master, it will truncate the string transmitted to your serial devices at this number of characters.

5.2.3 Setting up and Using Pad ModePad Mode operation is the method used by the DNET1CHCONV that adds extra characters to the end of its received data string (after the delimiter character) from the external I/O device before sending the string to the DeviceNet scanner (Master) as an I/O Response. The quantity added is such that the data string returned to the scanner is always a constant length – defined by the Max RX Char Length parameter. The quantity of pad characters sent can vary from message to message, depending upon the size of the incoming string.

Pad Mode Selection, Parameter 5

Pad mode is included with our device for compatibility with scanners that cannot receive variable length I/O messages. (Notable examples include Allen-Bradley’s scanners at the time of printing). For such scanners, you must keep Pad mode ON (a value of 1). Leaving Pad Mode ON will not harm scanners that do support variable length receive messages. The default value for Pad Mode is ON. If your scanner does support variable I/O messaging lengths, you may turn the Pad Mode option OFF (a value of 0) to conserve some network bandwidth.

The selection of Pad Mode is valid only for the DeviceNet message that the DNET1CHCONV produces. It has no effect on DeviceNet messages sent from the Scanner to the DNET1CHCONV. Parameter 5.

Pad Mode Character, Parameter 6

The DNET1CHCONV allows you to specify the character that pad mode uses to pad the received serial data. This can be set to any valid I/O value (0-127 in 7 bit modes, 0-255 in 8 bit modes).

Pad Mode is turned ON by default in the DNET1CHCONV.

5.2.4 Byte Swap ModeThis option may be helpful if the DNET1CHCONV is connected to a DeviceNet scanner that organizes the data string characters into data type elements that are larger than 1 byte each. (Examples are many Allen-Bradley PLCs, such as the SLC500.) In such cases the bytes of the

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data in the master’s memory organization can be reversed from the order in which they are sent or received on the DeviceNet and the serial link to the ASCII device. This may cause problems in some cases.

Example:

A barcode scanner recognizes a barcode marked “ABCDEFGH” and transmits this string to the serial device. The string will appear in memory as “BADCFEHG” for 2-byte word organization, and “DCBAHGFE” for 4-byte word organization. By enabling the respective swap mode, the DNET1CHCONV will rearrange the information so that it appears in the human readable “ABCDEFG” in the scanner’s data table.

Receive Byte Swapping, Parameter 7

By setting this parameter, the DNET1CHCONV will re-order the bytes received from your ASCII device before sending the string to the Master.

Transmit Byte Swapping, Parameter 14

By setting this parameter, the bytes from the Master will be swapped by the DNET1CHCONV before transmitting the string to the ASCII device.

Rules for Usage

1. Transmit and receive byte swapping are set and operate independently.

2. The byte swapping works better if the string length is an even multiple of the byte-swap size. You will loose the last characters in the string if this is not the case.

3. All other configuration parameters behave the same, independent of the swap mode.

4. Only the string data bytes are swapped – header bytes are not swapped.

5.2.5 Setting Up the Scanners I/O SizesThe DNET1CHCONV automatically calculates the number of bytes it sends to and receives from the DeviceNet Master. These values are determined by a combination of the incoming data and the Pad Mode selection (for Rx only). The gateway produce and consume parameters (Parameters 8 and 15) define the size of the DeviceNet messages sent and received by the DNET1CHCONV.

Set your scanner’s Consume (Input or Receive) size to Parameter 8.

Set your scanner’s Produce (Output or Transmit) size to Parameter 15.

IMPORTANT:

You will loose data if you do not set the scanner’s RX and TX values to the specified number of bytes in the parameter object.

IMPORTANT:

If you are using most Allen-Bradley scanners, you must set up the Scanner’s I/O mapping to exactly these sizes or the Scanner will take your DNET1CHCONV off-line and not re-connect.

5.2.6 Setting up the DeviceNet I/O ConnectionsIt is useful to first set up your serial link before setting up your connection. To set up the

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communications with your network configuration tool, it is often necessary to know the connection input and output sizes. Instructions for setting up your serial connection are provided above. See the sections on receive and transmit sizes.

If you are using a network configuration tool with some type of scanner or scanning software, you must direct your scanner to set up the connections for you. This often requires some information about the device, such as input and output sizes. The input and output sizes are computed from the transmit size and the receive sizes. These sizes are defined in the parameter object of your device. The transmit size of the poll connection is computed by adding 2 to the Transmit Buffer Size on the DNET1CHCONV. The Transmit size for the change of state and cyclic connections are set to 0, because these connections do not initiate a transmission on the serial link. The receive size of all three connections is computed by adding the number of option bytes to the Receive Buffer size. This final value is reported in Parameter 13.

Important: Remember to re-map the data (if necessary) after you set the sizes, because many configuration tools will automatically un-map your data when you change the connection sizes. If you are not using such a software package, it is probably not necessary to set up the transmit and receive sizes.

5.2.6.1 Polled I/OThe polled connection is the only manner in which you can send serial output data to the I/O and, therefore, to your I/O device. The DeviceNet Master initiates the polled connection transfer. The Master sends the DNET1CHCONV its serial output buffer along with a record number and length byte. The DNET1CHCONV monitors the record number for a change in the record number. If the record number changes, then the DNET1CHCONV transmits the data buffer on its serial link. If the record number does not change, then the device does not transmit the data buffer.

After the device has transmitted its data out to the serial link, the DNET1CHCONV then takes any information that is stored in its current serial input buffer and sends this data to the DeviceNet Master. It sends all characters up to and including the received delimiter, padding only if specified in the parameter object. When the DNET1CHCONV receives a new message (either with a delimiter or with an overflow condition without a delimiter) the device then increments the receive record, updates the length byte, and copies the new information from the last receive delimiter into the buffer. If an overflow occurs, the DNET1CHCONV indicates so in its receive status bit. The receive status byte also reflects parity errors in the device.

5.2.6.2 Cyclic and Change-of-State I/OThe Cyclic connection initiates a transmission every time the connection timer expires. The cyclic connection can only send data from the DNET1CHCONV. If you need to transmit on the I/O link, you will need to use the polled connection to do so. The polled and cyclic connections are not exclusive, so both can exist at the same time. The manner in which cyclic connection reports its data is the same as the polled connection. The cyclic connections transmit buffer is the same as the polled connections transmit buffer, so overflows and received delimiters act the same over any connection.

The Change of State (COS) connection is the same as the cyclic connection except that as well as triggering communications on the expiration of the timer, the COS connection also initiates a transfer on a receive of the delimiter or an overflow. The COS connection is mutually exclusive with the cyclic connection, but can coexist with the polled connection. The COS connection operation is very useful in conserving bandwidth, and provides the Master with the most current data as fast or faster than a poll connection. The COS connection automatically turns on the COS mechanism when the connection is created.

5.2.7 Setting up the DeviceNet Baud rateAutobaud is the mechanism that allows the DeviceNet device, in this case the DNET1CHCONV,

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to automatically determine the baud rate that is operational on the network to which the DNET1CHCONV is connected and to adjust its DeviceNet speed to match. The DNET1CHCONV is shipped with autobaud as its default baud rate.

If you wish to change the baud rate to a fixed speed, you can set it in two different places. 1) The first is in the DeviceNet object (Class 3). This is where most configuration tools will look to change the baud rate. 2) Because autobaud is not supported by the standard DeviceNet Object, the DNET1CHCONV provides a parameter to allow the autobaud selection. These values can be set and retrieved by using the standard Set and Get services.

5.3 Setting Up the Serial Link

5.3.1 Reception OverviewThe DNET1CHCONV receives a number of characters from the DeviceNet Master to your serial device via I/O Messaging or Explicit Messaging. Please note that the two forms of messaging are not designed to be used at the same time for communication; erroneous operation will occur when both IO and explicit messaging are used at the same time to control serial receptions.

The DNET1CHCONV receives characters into its internal character queue. The DNET1CHCONV then takes the first character out of the queue and places it into the back receive buffer. If the character that was placed into the back buffer is the Receive End Delimiter or the back buffer contains the Max Receive Length of characters, The DNET1CHCONV will copy the back buffer into the Receive Buffer and change the Receive Transaction Identifier (RXID) to notify the PLC that new data is ready.

Section 5.4.2 describes the Receive Swap settings

Section 5.3.4 describes the Receive End delimiter Settings

Appendix A describes the receive formatting object in more detail.

It is important to note that the IO assembly object does not process the content of the data given it. It only disassembles the received data and assembles the outgoing data to/from other logical sources in the device. Due to the nature of DeviceNet messaging, a field changed by an explicit message that is also set by an IO message will change momentarily to the explicit value and then immediately change back to the IO data. This will cause erroneous operation of the device. In short, if you wish to use explicit messaging for I/O, do not allocate an I/O connection.

5.3.2 Transmission Overview The DNET1CHCONV transmits a number of characters from the DeviceNet Master to your serial device via I/O Messaging or Explicit Messaging. Please note that the two forms of messaging are not designed to be used at the same time for communication; erroneous operation will occur when both IO and explicit messaging are used at the same time to control serial transmissions.

The DNET1CHCONV will transmit the current data in the Transmit Buffer whenever the Transmit Transaction Identifier (TXID) is changed. These fields may be changed explicitly and are also available in the IO messages. The information that is stored in the Transmit Buffer is first parsed by the DNET1CHCONV, which changes the order of data based on the setting of the Transmit Byte Swap and the amount of data sent based on the setting of the Transmit End Delimiter. The Transmit Byte swap option is used to align the data to your PLC’s data table. The maximum amount of information that will be received at one time is determined by the Transmit Character Buffer Length (in the device net set up).

Section 5.4.2 describes the Transmit Swap settings

Section 5.3.5 describes the Transmit End delimiter Settings

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Appendix A describes the transmit formatting object in more detail.

It is important to note that the IO assembly object does not process the content of the data given it. It only disassembles the received data and assembles the outgoing data to/from other logical sources in the device. Due to the nature of DeviceNet messaging, a field changed by an explicit message that is also set by an IO message will change momentarily to the explicit value and then immediately change back to the IO data. This will cause erroneous operation of the device. In short, if you wish to use explicit messaging, do not allocate an IO connection.

Note:

If you set the Tx Buffer Length to 0 and the DNET1CHCONV receives more than the number of bytes defined in Max TX Buffer Length in a consumed DeviceNet message from the Master, the DNET1CHCONV will drop the I/O connection or return an error of “too much data”.

5.3.3 Physical Layer PropertiesThe Physical Layer properties such as the framing, stop bits, data bits, parity options and baud rate may be set at parameters 1 and 2 of the DNET1CHCONV.

5.3.4 Hardware HandshakingYou may select to activate the hardware handshaking option between the DNET1CHCONV and your serial device if your serial device supports RTS/CTS handshaking operation. The RTS and CTS lines (pins 7 and 8, respectively, on the D-sub connector) interface with the corresponding CTS and RTS lines on your serial device.

5.3.5 The Receive Delimiter When receiving data strings from your serial device, the DNET1CHCONV can take advantage of a Stop (End) delimiter. The End Delimiter is the end-of-string indicator. This allows you control over exactly which characters are sent to the Master. The DNET1CHCONV is always storing a string into its internal buffer. All characters are stored until either the End Delimiter is received or the Max Receive Char Length is reached (This is the end event). Once either of these end events occurs, the data string is captured and sent to the master. The delimiter, if received, is included in the received string.

Note:

Please note that the Receive Delimiter operation is always active, unlike the Transmit Delimiter operation (described below), which can be enabled or disabled. If you want to receive a constant string equal to the Max Receive Length, and do not want the delimiter operation to initiate a partial produce on DeviceNet, then make sure your serial device does not send the designated Rx Delimiter Character.

5.3.6 The Transmit DelimiterThe transmit delimiter is an optional feature which can be used by the DNET1CHCONV to determine how many bytes to transmit over the serial link.

The Transmit Delimiter operation is keyed off the Transmit Buffer Length byte in the DeviceNet data that the DNET1CHCONV consumes from the Master. This Transmit Buffer Length byte is the second byte in the consume assembly. See Table 6-13.

The Transmit Delimiter will be used if the Transmit Buffer Length equals 0 . If the Tx Buffer Length is a non-zero value, the DNET1CHCONV will ignore the transmit delimiter and transmit the specified number of bytes.

The transmit delimiter can be set to any valid I/O character that can be received over the link. Be

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very careful not to set the delimiter to a value outside of the valid range for your data bits (Note: A data bit size setting of 7 will only allow you a delimiter range of 0-127 dec., 00-7Fhex). If you do not have the specified delimiter in the string you send to the DNET1CHCONV and the TX Length is not 0, the DNET1CHCONV will transmit the entire received message. If your PLC or PC Master device does not support variable length IO messages, this will have the effect of putting garbage characters at the end of your string.

5.3.7 Status Byte DescriptionThe Serial Status byte is an OR’d bit field of a number of status and exceptions. Bits 5-7 are undefined.

Table 5-12 Serial Status Byte

Bit Exception0 TX Buffer Overflow1 RX Buffer Overflow2 RX Parity Error3 Tx Buffer Has Data4 Rx Buffer Has Data

TX Buffer Overflow

The transmit queue has overflowed resulting in a loss of data. The transmit I/O is full of data waiting to be transmitted. Some of the data added has been lost. When space becomes available in the TX Buffer, this bit will be reset.

Rx Buffer Overflow

The receive queue has overflowed resulting in a loss of data. The receive buffer is full of data waiting to be processed. The data has been lost. When space becomes available in the RX buffer, this bit will be reset.

Receive error

The receive error detection circuit has detected an invalid byte on the serial port. This character has been ignored. The Parity error bit will be reset when the message that contained the error is released.

Data in Tx Buffer

The Transmit Serial Data Buffer has new message data that it has sent out the serial link.

Data in Rx Buffer

The Receive Serial Data Buffer has new message data that it has not produced onto the DeviceNet link.

6. Assembly Object FormatsThe individual serial channels are read and written one channel per message.

The produce (receive) and consume (transmit) assembly object formats vary according to 2 specific parameter options: the Data Type and the Handshaking / Immediate Mode operation.

In this discussion “consume” and “produce” refer to data received from and sent out to the

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DeviceNet network by the DNET1CHCONV.

For this mode to work correctly in many PLCs with a scanner, the outgoing poll message must be constructed in a buffer, and when complete, should then be copied whole to the scanner’s file.

6.1 Assemblies

Table 6-13 Consume Assembly

Reserved Reserved TXIDTransmit

Buffer Length

String byte #1

String byte #2

String byte #3

String byte N

Table 6-14 Produce Assembly

Reserved RXID StatusReceived

Buffer Length

String byte #1

String byte #2

String byte #3

String byte N

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A. Theory of OperationA.1 The Transmit Record Algorithm

A.1.1 Basic Theory of operationThe Transmit record object addresses several issues of utilizing a DeviceNet network device in the process of communicating via a serial data stream. The device takes a block of data passed by the I/O and transmits this data out over the DeviceNet link. A Transaction ID, providing control of data sent from the DNET1CHCONV, can protect this data.

The data flow and algorithm are shown below for reference.

Figure A-5 Transmit Record Algorithm Functional Flowchart

As diagramed above, the serial data is set and then parsed if the serial data length is set to zero. The parser then sets the length on the serial data. If Record Protection is disabled, the data is immediately added to the serial port’s transmit queue. Also, whenever the Transaction Id is changed, the serial transmit data is sent to the serial port object.

The parser determines the length of the string by searching the string for a delimiter character. The algorithm can be configured to ignore, include or exclude the character.

A.2 The Receive Record AlgorithmThe receive record algorithm was developed in order to enable the receipt of data from a remote serial device and the subsequent transmission of data over a DeviceNet I/O connection. The Receive Record Algorithm controls when data is acquired and when that acquired data is presented to the connection. This section will help you understand the algorithm in order to efficiently utilize all of the capabilities of the DNET1CHCONV.

A.2.1 Basic Theory of operation The Basic function of the DNET1CHCONV is to address the problem of receiving and transmitting serial data over DeviceNet. Serial data is a data stream, in which data is presented to a device one byte at a time and does not have a beginning or an end. DeviceNet however, is not stream oriented; data is presented in chunks of defined sizes and bounds. The Receive

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Serial PortObject

Serial Data

Transaction ID

Data Switch

Record Enabled?

Parser


Record algorithm formats the streaming data into a data block. It uses user-defined events on the receive serial link to determine where this data block starts and ends. It then uses a status byte to notify the controlling DNET1CHCONV when new data is available. The DNET1CHCONV then increments the record number and the new data are presented.

The Receive Record Algorithm creates a DeviceNet object and presents the data in an ordered fashion to the DeviceNet I/O connection. The Receive Record object may be reached over DeviceNet at Class 0x72. If you are going to be using explicit messaging to communicate with the device, we recommend that you access the data from this point, and not the parameter object, because the parameter object obeys slightly different rules in order to ease the interface with today’s most common configuration tools.

Figure A-6 Receive Record Algorithm Functional Flowchart

The Receive Record Algorithm is diagramed above. The serial stream originates from the serial port object (0x70). It is looked at a byte at a time by the event detection system. If the event detection system detects a beginning event (the beginning delimiter is received or disabled), it closes the first data switch, allowing the serial data to accumulate in the back buffer. Once an end event is received (the End delimiter is received, or the back buffer is full) the event detection system will close the data switch and set a new data status. When the new data status is set, if the device is set up in auto increment mode, the object will automatically increment the record number and clear the new data bit. In this configuration, the user will not be allowed to set the Receive Record Number.

The SHORT_STRING data type is the DeviceNet data type used in the DNET1CHCONV. This data type has a 1-byte length.

The DNET1CHCONV is supported by a variety of DeviceNet. Short poll responses save bandwidth on the DeviceNet network, but many scanners do not support this functionality and will not allow communication with a device that responds in this manner. The DNET1CHCONV supports this non-compliant behavior through pad mode. This is a function where a character is appended to the end of the serial data in order to fill out the poll response. The default for pad mode is OFF, and the default for the pad character is 0 (NULL).

Note: Turn pad mode ON if you receive errors indicating that the I/O data response is too short.

The DNET1CHCONV also supports byte-reordering to support multi-byte PLC files. The DeviceNet network data-ordering scheme is little ending, meaning that the low byte of a multi-byte messages transmitted first. This means that if you are using a data file that is using a 16 bit or larger word size and you map the connection’s data directly into this space, your data bytes

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Serial Port Object

Data SwitchBack Buffer

DataSwitch

Received Data Serial Data

Event Detection System

Record Number

Auto Inc?

Status Byte

Record Change

End Event

Begin Event


will show up swapped. The DNET1CHCONV implements byte reordering (swapping) in order to accommodate these PLCs. The swapping mechanism re-orders the I/O data so that is appears in a human readable form in a file with a little ending byte order. To enable byte swapping, determine the number of bytes in your data size. Subtract 1 from this number, and set the Receive Record object’s byte swapping attribute to this value (also available through the parameter object). Now, you must set the length of your message size to a multiple of 1+this value, or the DNET1CHCONV will not be able to swap the bytes correctly. The data will now be ordered properly in your DNET1CHCONV.

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B. DeviceNet Profile, Objects and Services B.1 DNET1CHCONV DeviceNet Profile

This section describes the DeviceNet Objects present in the I/O. The I/O conforms to a Type 12, Communications Adapter Device.

Table B-15 DeviceNet Objects

Object DeviceNet Object Class # of Instances

Identity 1 1

Message Router 2 1

DeviceNet 3 1

Connection 5 3 (Explicit Msg., Polled I/O, COS/Cyclic)

Parameter 15 (Fhex) 20

Serial Port 112 (70hex) 1

Serial Transmit 113 (71hex) 1

Serial Receive 114 (72hex) 1

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B.2 Assembly Object FormatsTable B-16 Poll Produce Data (ASCII Receive String)

Byte Character Description0 Null (0) Reserved1 RXId Receive Transaction ID, Integer value 0 –

255(0 = Initialized State)

2 Status Status / Error Value3 Length Length of valid data in bytes4 1st Char ASCII Character5 2nd Char ASCII Character Last Char ASCII Character Terminator End-of-Text Character Any Pad character (present if characters received

is less than Max Receive Chars value) Any Pad character (present if characters received

is less than Max Receive Chars value)

Table B-17 I/O Consume Assembly Format (ASCII Transmit String)

Byte Character Description0 Null (0) Reserved1 Null (0) Reserved2 TXID Transmit Transaction ID, Integer value 0 –

255(0 = Initialized State)

3 Length Number of bytes to transmit. 0 indicates transmit delimited mode, in which the device

transmits up to and including the transmit delimiter character defined in the parameter

object.4 1st Char ASCII Character5 2nd Char ASCII Character6 3rd Char ASCII Character Last Char ASCII Character Terminator End-of-Text Character Any Undefined Any Undefined

(last char in this record transmitted to Master)

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B.3 Identity Object, Class 1Instances 0 and 1 exist in the DNET1CHCONV.

Table B-18 Identity Object Class Attributes (Instance 0)

Attribute ID

Access Rule Name DeviceNet

Data Type Description of Attribute DefaultValue

1 Get Revision UINT Revision of this object 1

2 Get Max. Object Instance UINT Maximum instance number of an

object currently 1

6 GetMax. Class Attribute ID UINT

Attribute ID number of the last class attribute of the class definition implemented in the device

7

7 GetMax. Instance Attributes ID UINT

Attribute ID number of the last instance attribute of the class definition implemented in the device

1

Table B-19 Identity Object Instance Attributes (Instance 1)

Attribute ID


Data Type Description of Attribute Value

1 Get Vendor UINT ODVA Vendor Number for this product 8 = SST

2 Get Device Type UINT ODVA Communications Device Type 12 = Comm.

Adapter

3 Set Product Code UINT SST Unique Product Code Number 102 dec

4 Get Revision STRUCT of: Revision of this deviceMajor Revision USINT 1

Minor Revision USINT 4

5 Get Status WORD Summary status of device

6 Get Serial Number UDINT WC Unique Device Serial Number

7 Get Product Name

SHORT_STRING ASCII Name of product DNET1CHC

ONV

10 Get/Set Heartbeat Interval USINT

The interval in second that the device generates a heartbeat message. A value of 0 disables heartbeat generation.

0

Table B-20 Identity Object Common Services

Service Code Class Instance Service Name Description of Service

O5 hex Yes Yes Reset Invokes the Reset Service for the device.

OE hex Yes Yes Get_Attribute_Single Returns the contents of the specified attribute.

10 hex No Yes Set_Attribute_Single Modifies an attribute value.

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B.4 Parameter Object, Class Fhex (15dec)There are many configurable data parameters associated with your DNET1CHCONV. The DNET1CHCONV uses a Parameter Object (a collection of these parameters) to assist you in reading and changing configurable data.

Following are the Class Attributes, Instance Attributes and Services that are supported by the DNET1CHCONV for the Parameter Object.

Table B-21 Parameter Class Attributes (Instance 0)

Attribute ID


Data Type Description of Attribute Value

1 Get Revision UINT Revision of this object. 1

2 Get Max. Instance UINT Maximum instance number of

the Parameter object 19

8 GetParameter class descriptor

WORD Bits that describe parameters.

9 (supports parameter instances, prams are stored in non-volatile

memory)

Table B-22 Parameter Instance Attributes (Instances 1-7)

Attribute ID

Access Rule Name DeviceNet Data Type Description of Attribute Value

1 Set Parameter Value

data type specified in Descriptor Data Type

and Data Size.

Actual value of parameter. It can be read from or written to. This attribute is read-only if bit 4 of Attribute 4 is TRUE.

2 Set Link Path Size USINT Size of link path. If this is 0, then

no link is specified.Number of bytes

3 Set Link Path ARRAY of DeviceNet path:

DeviceNet path to the object from where this parameter’s value is retrieved.

4 Get Descriptor WORD Description of parameter.5 Get Data Type USINT Data type code.

6 Get Data Size USINT Number of bytes in Parameter Value

Table B-23 Parameter Common Services

Service Code Class Instance Service Name Description of Service

O5 hex Yes Yes Reset Resets all parameters to “out-of-the-box” values.

OE hex Yes Yes Get_Attribute_Single Returns the contents of the specified attribute.

10 hex Yes Yes Set_Attribute_Single Modifies an attribute value.

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B.5 Serial Port Object (0x70)Table B-24 Serial Port Object Instance Attributes

ParameterParam. Instanc

eAccess Description Parameter Choices Default


Data Type

Status 1 Get Serial port status1 – TX I/O Overflow2 – Rx I/O Overflow4 – Rx Parity Error

OK 0 BYTE

Reserved 2 N/a

Reserved 3 N/a

Serial Character Framing Format

4 Get/Set Character framing

0 = 7N21 = 7E12 = 7O13 = 8N14 = 8N2

5 = 8E16 = 8O17 = 7E28 = 7O2

8N1 0 USINT

Serial Baud Rate 5 Get/Set

I/O/ I/O communications

speed

0 =96001 = 12002 = 24003 = 4800

4 = 19.2k5 = 38.4k6 = 57.6k7 = 115.2k

9600 baud 0 USINT

Notify Rx Path 6 Get

Object to notify when receive events

happenEPATH NULL EPATH

Notify Tx Path 7 Get

Object to notify when transmit events

happenEPATH NULL EPATH

B.6 Transmit Record Object, Class 113 (0x71)

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Table B-25 Transmit Record Object Instance Attributes

Parameter Param. Instance Access Description Parameter Choices Default


Data Type

Hardware Interface Instance

1 Get Serial port number 1 1 1 USINT

Tx Record Number 2 Get

Record number assigned to the last received data string

0-255 0 0 USINT

String Data 3 Get Last received serial data received N/a None 0 USINT

Data String Type 4 Get/Set Format of data

0 = Array1 = Short_String2 = String

Array 0 USINT

Max Number of Receive

Chars5 Get/Set

Maximum number of characters the 1782-I/O expects to receive into its I/O port from the

serial device


Receive End Delimiter 6 Get/Set

Character which identifies the end of the data string from the I/O device when the length

is specified as 0

Any valid standard I/O character

(0 – 127, 0-255)


Receive Record End Mode 7 Get/Set

Selects If the transmit delimiter is used,

included in the data string or excluded in the

resultant data string

0 =No Delimiter1 = Exclude the delimiter 2 = Include The delimiter

Include 2 USINT

DeviceNet Handshake

Mode8 Get/Set

Defines if the received string is sent

immediately to master (in poll mode) or after a

I/O handshake ACK

0 = No DeviceNet handshaking; produce data

immediately1 = produce after I/O

handshake

No DeviceNet handshake

0 USINT

Receive Swap Mode 9 Get/Set


messages will be swapped every 2 or 4

bytes.


Disabled 0 USINT

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Status 10 GetStatus of the Record

Object No Error 0 BYTE

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B.7 Receive Record Object, Class 114 (0x72)Table B-26 Receive Record Object Instance Attributes

Hardware Interface Instance

1 GetInstance of the serial port object that we

listen to1 1 1 USINT

Rx Transaction ID 2 Get/Set

Record number assigned to the last received data string

0-255 0 0 USINT

Rx Data 3 Get Last received serial data N/a None 0 USINT

Rx Data Format 4 Get/Set Format of data

0 = Array1 = Short_String2 = String

Short String 1 USINT

Pad Mode 5 Get/Set

Indicates whether to pad the invalid data

region after the delimiter with the pad

character, or to use variable length I/O

responses

0 = Pad Mode Disabled1= Pad Mode Enabled

Embedded 1 USINT

Pad Character 6 Get/SetThe value to use to pad the invalid data portion

of the poll response


(0 – 127, 0-255)NULL 0 USINT

Max Number of Rx Chars 7 Get/Set

Maximum number of characters the gateway expects to receive into its I/O port from the

serial device


Start Delimiter Char 8 Get/Set

Character which identifies the beginning of the data string from

the I/O device when the length is specified as 0


(0 – 127, 0-255)


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Stop Delimiter Char 9 Get/Set

Character which identifies the end of the data string from the I/O device when the length

is specified as 0


(0 – 127, 0-255)


Start Delimiter Mode 10 Get/Set

Selects whether or not the beginning delimiter is included in the data

string

0 = No Delimiter 1 = Exclude Delimiter2 = Include Delimiter

No Delimiter 0 USINT

Stop Delimiter Mode 11 Get/Set

Selects whether or not the end delimiter is included in the data

string

0 =No Delimiter1 = Exclude Delimiter2 = Include Delimiter

Include 2 USINT

Swap Mode 12 Get/Set


messages will be swapped every 2 or 4

bytes.


Disabled 0 USINT

Immediate / Handshake

Mode13 Get/Set

Defines if the received string is sent

immediately to master (in poll mode) or after a

I/O handshake ACK

0 = Set New Data Status Bit and wait for I/O to increment

record number1 = Automatically increment

the record number and show the new data when an

end event is received

Auto Increment 1 USINT

New Data Status 14 Get Status of the Record

object Bit 7 – New Data Available No Status 0 BYTE

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B.8 Common DeviceNet ServicesDeviceNet is divided into logical functional blocks called objects, which provide services that allow for control over the hardware and routines that those objects contain. To allow for multiple similar functions, the objects are built of multiple instances that the services of the objects act upon. A class service acts upon the entire object, allowing one service to be enacted on all of the instances. This saves time, effort and network bandwidth.

The common services are a common set of services that have been provided in most or all of the objects to allow for common functionality in creating, deleting, getting, setting and resetting the variables of the different classes and instances. We will describe two of the services here: get and set.

The get and set services have a common format for specifying what object, instance, attribute and service that the command is specifying. In order of first to last, DeviceNet specifies service, class, instance, attribute and data. The data is always little ending (low byte precedes high order byte), and the others are all one byte in length on the DNET1CHCONV. Note that the get service has no data.

The get service gets data from an attribute of a class or class instance. The service number of this request is 14 (E hex). The class instance and attribute are all defined by which variable you want to get. The response from a get command takes on the form: service, value. The value will be little ending and can be of variable length and bounds based on the definition of the attribute. The service will be reported as the get service with the highest bit set to indicate a response.

The set service sets data from an attribute of a class or class instance. The service number of this request is 16 (10 hex). The class instance and attribute are all defined by which variable you want to set. The value is little ending, and the size is defined by the attribute that you are setting. The response from a set command only echoes the service. The service will be reported as the set service with the highest bit set to indicate a response.

An error response will have the service set to 94hex. This response will be followed by a two-byte error code, defining the type of fault. For a detailed list of error codes, connect to the ODVA web site at www.odva.org.

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DNET4CHCONV User Manual - Molex Users... · Web viewObject DeviceNet Object Class # of Instances Identity 1 1 Message Router 2 1 DeviceNet 3 1 Connection 5 3 (Explicit Msg., Polled