Rockwell Automation 1799-DASCII User Manual

Installation Instructions

DeviceNet Serial Interface Module

Catalog Number 1799-DASCII

Top ic Pa ge

Important User Information 2
Environment and Enclosure 3
Prevent Electrostatic Discharge 3
About the Module 4
Install the Module 5
Set the Node Address 5
Mount the Board 6
Product Dimensions 7
Set Up the DeviceNet I/O Connections 7
DeviceNet Wiring 10
Serial Port DB9 Wiring 10
Set Software Parameters + 12
Configuring the Parameters 19
Set Up the Serial Link 19
Receive Serial Data from the ASCII Device 21
Produce Received-serial Data onto DeviceNet Network 23
Set Up and Use Pad Mode (parameters 11 and 12) 24
Set Up and Use the Swap Bytes Mode (parameter 13) 25
Serial Status Byte Description and Transmission 27
Consume Data Assembly Formats from DeviceNet Master 28
Transmit Serial Data to the ASCII Device 30
Status Indicators 32
Specifications 33

2 DeviceNet Serial Interface Module

Important User Information

Solid state equipment has operational characteristics differing from those of electromechanical equipment.
Safety Guidelines for the Application, Installation and Maintenance of Solid State Controls (Publication
SGI-1.1 available from your local Rockwell Automation sales office or online at
http://literature.rockwellautomation.com
equipment and hard-wired electromechanical devices. Because of this difference, and also because of the
wide variety of uses for solid state equipment, all persons responsible for applying this equipment must
satisfy themselves that each intended application of this equipment is acceptable.

In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages
resulting from the use or application of this equipment.

The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many
variables and requirements associated with any particular installation, Rockwell Automation, Inc. cannot
assume responsibility or liability for actual use based on the examples and diagrams.

No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits,
equipment, or software described in this manual.

Reproduction of the contents of this manual, in whole or in part, without written permission of Rockwell
Automation, Inc., is prohibited.

Throughout this manual, when necessary, we use notes to make you aware of safety considerations.

) describes some important differences between solid state

WARNING

IMPORTANT

ATTENTION

SHOCK HAZARD

BURN HAZARD

Identifies information about practices or circumstances that can cause an explosion in
a hazardous environment, which may lead to personal injury or death, property
damage, or economic loss.

Identifies information that is critical for successful application and understanding of
the product.

Identifies information about practices or circumstances that can lead to personal injury
or death, property damage, or economic loss. Attentions help you identify a hazard,
avoid a hazard and recognize the consequences.

Labels may be on or inside the equipment (for example, drive or motor) to alert people
that dangerous voltage may be present.

Labels may be on or inside the equipment (for example, drive or motor) to alert people
that surfaces may reach dangerous temperatures.

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Environment and Enclosure

DeviceNet Serial Interface Module 3

ATTENTION

This equipment is intended for use in a Pollution Degree 2 industrial environment, in
overvoltage Category II applications (as defined in IEC publication 60664-1), at altitudes
up to 2000 m (6562 ft.) without derating.

This equipment is considered Group 1, Class A industrial equipment according to
IEC/CISPR Publication 11. Without appropriate precautions, there may be potential
difficulties ensuring electromagnetic compatibility in other environments due to
conducted as well as radiated disturbance.

This equipment is supplied as open type equipment. It must be mounted within an
enclosure that is suitably designed for those specific environmental conditions that will
be present and appropriately designed to prevent personal injury resulting from
accessibility to live parts. The interior of the enclosure must be accessible only by the use
of a tool. The enclosure must have suitable flame-retardant properties to prevent or
minimize the spread of flame, complying with a flame spread rating of 5VA, V2, V1, V0 (or
equivalent) if nonmetallic. Subsequent sections of this publication may contain additional
information regarding specific enclosure type ratings that are required to comply with
certain product safety certifications.

In addition to this publication, see:

• Industrial Automation Wiring and Grounding Guidelines, Allen-Bradley publication

1770-4.1, for additional installation requirements.

• NEMA Standards publication 250 and IEC publication 60529, as applicable, for

explanations of the degrees of protection provided by different types of enclosure.

Prevent Electrostatic Discharge

ATTENTION

This equipment is sensitive to electrostatic discharge, which can cause internal damage
and affect normal operation. Follow these guidelines when you handle this equipment:

• Touch a grounded object to discharge potential static.

• Wear an approved grounding wriststrap.

• Do not touch connectors or pins on component boards.

• Do not touch circuit components inside the equipment.

• Use a static-safe workstation, if available.

• Store the equipment in appropriate static-safe packaging when not in use.

ATTENTION

To comply with the CE Low Voltage Directive (LVD), the DeviceNet network must be
powered from a source compliant with Safety Extra Low Voltage (SELV) or Protected
Extra Low Voltage (PELV).

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4 DeviceNet Serial Interface Module

ATTENTION

To comply with UL restrictions, the DeviceNet network must be powered from a source
compliant with a Class 2 or UL Listed/recognized power supply with isolated outputs
limited to 200 volt-amperes in each ungrounded output line. This equipment and its
power source must be mounted in a suitable enclosure with proper spacings maintained.

About the Module

The 1799-DASCII module provides DeviceNet system interoperability to one RS-232
or multiple RS-485 devices that do not have DeviceNet network capability. The
DeviceNet port (J1) provides power to the module and DeviceNet network
communication. The serial communication port (J2) is isolated from the DeviceNet
network and the module logic power.

J1

J2

44322

The 1799-DASCII module supports modes of data transfer of the serial buffer that
include the following:

• Polled I/O

• Change-of-State I/O

• Cyclic I/O

• Explicit Message

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DeviceNet Serial Interface Module 5

Mating connectors and mounting hardware are optional and must be ordered
separately. This table identifies these optional connectors and hardware.

Optional Connectors and Hardware

Option Catalog Number Supplier and Part Number

2 DIN-rail brackets (4 screws) 1799-BRKD N/A

5-position, open-style plug for DeviceNet
network (2 locking screws)

1799-DNETSCON

DeviceNet Buyer’s Guide at
http://www.odva.org

Your package contains:

• one 1799 I/O board.

• installation instructions.

Install the Module

Follow these steps to install the module.

1. Set the node address.

2. Mount the board by using brackets or mounting screws.

3. Connect serial communication cable (232 or 485) to DB9 connector.

4. Connect the DeviceNet network and DeviceNet power to the unit.

5. Configure the parameters.

Set the Node Address

Valid node addresses are 00…63.

Set the node address by using the rotary switches or a DeviceNet configuration tool
such as RSNetWorx for DeviceNet software. The software has address control when
you set the switches to 64…99.

Each board is shipped with the node address set to 63 in the board’s memory;
rotary switches are shipped with the node address set to 99. The switches are near
the center of the board. The two switches are as follows:

• MSB (most significant bit)

• LSB (least significant bit)

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6 DeviceNet Serial Interface Module

To reset the node address, use a screwdriver to rotate the switches. Align the small
arrow on the switch with the number setting you wish to use.

MSB

The LSB and MSB switches are
shown in the 63 position.

LSB

42558

The rotary switches are read when you apply power to the board. The board uses
the last valid node address stored in board memory when you set the switches to
64…99. For example, the last setting in memory is 40. If you change the switch
setting to 68 and apply power to the board, the address defaults to 40.

The board is equipped with AutoBaud detect. With AutoBaud, the board detects
the communication rate on your DeviceNet network and automatically adjusts to
that rate. The board is shipped with AutoBaud enabled.

Mount the Board

You can mount the board to a DIN rail by using DIN-rail brackets (catalog
number 1799-BRKD) or to a mounting plate.

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44623

DeviceNet Serial Interface Module 7

You can also mount the board in an enclosure with pretapped holes to
accommodate M3 x 0.5 mm screws.

Product Dimensions

See the drawing that shows product dimensions.

Dimensions are in mm (in.).

mm
(in.)

18.8
(0.74)

16
(0.63)

11.43
(0.45)

127 (5.0)

67.3 (2.625)

50.8
(2.00)

31.75 (1.25)

67.3 (2.625)

44323

Set Up the DeviceNet I/O Connections

Set up the serial link before setting up the connection. To set up communication
with the network configuration tool, you typically need to know the connection
input and output sizes.

See Set Up the Serial Link on page 19 for instructions on setting up the serial
connection and receive and transmit sizes.

If you are using a network configuration tool with some type of scanner or
scanning software, the scanner must be directed to set up the connections. This
often requires some device information, such as input and output sizes. The input
and output sizes are computed from the transmit and receive sizes. These sizes are
defined in the parameter object of the device. The transmit size of the poll
connection is computed by adding 2 to the transmit buffer size on the 1799-DASCII
module. 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.

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8 DeviceNet Serial Interface Module

IMPORTANT

Remember to remap the data (if necessary) after setting the sizes, because
many configuration tools automatically unmap data when the connection sizes
change.

The 1799-DASCII module supports modes of data transfer of the serial buffer that
include the following:

• Polled I/O

• Change-of-state I/O

• Cyclic I/O

• Explicit Message

Polled I/O

The polled connection is the only way you can send serial output data to the I/O
and I/O devicce. The DeviceNet master initiates the polled connection transfer.
The master sends the 1799-DASCII module its serial output buffer with a record
number and length byte. The 1799-DASCII module monitors the record number for
a change. If the record number changes, the 1799-DASCII module transmits the
data buffer on its serial link. If the record number does not change, the device
does not transmit the data buffer.

After the device has transmitted its data out to the serial link, the 1799-DASCII
module 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
1799-DASCII module receives a new message with a delimiter or with an overflow
condition without a delimiter), the device 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 1799-DASCII module indicates so in its
receive status bit. The receive status byte also reflects other errors in the device.

Cyclic I/O

The cyclic connection initiates a transmission every time the connection timer
expires. The cyclic connection can only send data from the 1799-DASCII module. If
you need to transmit on the I/O link, the polled connection is necessary. The
polled and cyclic connections can exist simultaneously. 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.

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DeviceNet Serial Interface Module 9

Change-of-State I/O

The change-of-state (COS) connection is the same as the cyclic connection except
that the COS connection also initiates a transfer on the receipt 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
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.

Set Up the Connection Timer

The 1799-DASCII module sets the connection timer to the expected packet rate
(EPR), sometimes referred to as scan rate, value for the cyclic and polled
connection. It also uses this value in the connections to calculate the time the
device waits before signaling a timeout. If you are using a scanner or scanning
software, the EPR must be configured. The scanner configures the EPR in the
1799-DASCII module at the beginning of communication. Refer to the scanner
manual for how to configure the EPR.

IMPORTANT

The EPR can be set manually by performing a set (Service 10hex) on the
connection class (Class 5hex) attribute 9. The polled connection uses
instance 2. The COS and cyclic connections use instance 4. This must be done
after allocating the connection.

Serial Data Strings and the Scanner's I/O Rate

Serial gateways typically use more bandwidth on the DeviceNet bus than other
types of I/O devices. If long data strings are implemented and/or multiple devices
are on the DeviceNet network, make sure the scan rate is set accordingly.

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10 DeviceNet Serial Interface Module

DeviceNet Wiring

DeviceNet wiring connections are made to the plug-in connector. The connector
plugs into connector J1 on the circuit board.

Network Connector (female contacts)

5 V+ Red
4 CAN_H White
3 Drain Bare
2 CAN_L Blue
1 V- Black

Network Connector (male contacts)

Serial Port DB9 Wiring

The module operates as an RS-232 or RS-485 device, depending on how the serial
communication lines are attached. For information about serial port connections,
see the DB9 9-Pin Connector Signal Assignments table and description. All signal
lines are isolated.

Serial Port Connection

The ASCII devices are connected to the 1799-DASCII module by using a three-wire
(or five-wire for RS232 hardware handshaking) communication cable.

DB9 9-Pin Connector Signal Assignments

Pin RS-232 RS-485

1 TRXD-

2RX

3TX

4

5 Common Common

6

7RTS

8CTS

9 TRXD+

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DeviceNet Serial Interface Module 11

RS-232 without Hardware Handshaking

Follow these steps to connect the RS-232 wiring without hardware handshaking.

1. Connect the receive wire to pin 2 (RXD).

2. Connect the transmit wire to pin 3 (TXD).

3. Connect common to pin 5 (common).

The channel automatically operates in RS-232 mode when these pins are
connected.

The RS-232 electrical interface uses a MAX232 transceiver or electrical equivalent.

IMPORTANT

All pins are active. Do not connect to other pins.

RS-232 with Hardware Handshaking

When implementing RTS/CTS handshaking, follow these steps to connect RS-232
wiring.

1. Connect receive to pin 2 (RXD).

2. Connect transmit to pin 3 (TXD).

3. Connect transmit/handshaking to pin 7 (RTS).

4. Connect receive/handshaking to pin 8 (CTS).

5. Connect common to pin 5 (Common).

The channel automatically operates in RS-232 mode when these pins are
connected.

IMPORTANT

All pins are active. Do not connect to other pins.

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