DeviceNet Serial Interface Module...6 DeviceNet Serial Interface Module Publication 1799-IN012B-EN-P - July 2008 To reset the node address, use a screwdriver to rotate the switches

Installation Instructions

DeviceNet Serial Interface Module

Catalog Number 1799-DASCII

Topic Page

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) describes some important differences between solid state 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.

WARNINGIdentifies 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.

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

ATTENTIONIdentifies 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.

SHOCK HAZARD

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

BURN HAZARD

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

Publication 1799-IN012B-EN-P - July 2008

http://literature.rockwellautomation.com

DeviceNet Serial Interface Module 3

Environment and Enclosure

Prevent Electrostatic Discharge

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.

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).



About the ModuleThe 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.

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

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.

44322

J2

J1



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

Your package contains:

• one 1799 I/O board.• installation instructions.

Install the ModuleFollow 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 AddressValid 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)

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


http://www.odva.org


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.

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.

MSB

LSB

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

42558

44623



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

Product DimensionsSee the drawing that shows product dimensions.

Set Up the DeviceNet I/O ConnectionsSet 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.

44323

mm(in.)

11.43(0.45)

67.3 (2.625)

127 (5.0)

50.8(2.00)

31.75 (1.25)

16(0.63)

18.8(0.74)

67.3 (2.625)

Dimensions are in mm (in.).



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.

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



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.

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.

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.



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

Serial Port DB9 WiringThe 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-

2 RX

3 TX

4

5 Common Common

6

7 RTS

8 CTS

9 TRXD+

Network Connector (female contacts)

Network Connector (male contacts)

5 V+ Red4 CAN_H White3 Drain Bare2 CAN_L Blue1 V- Black



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.

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.

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



RS-485 Mode

To operate in RS-485 mode, follow these steps.

1. Connect TRXD+ to pin 9.

2. Connect TRXD- to pin 1.

3. Connect common to pin 5.

The channel automatically operates in RS-485 mode by connecting these pins.

Set Software ParametersThe 1799-DASCII module is configured by using the EDS parameters as defined in the EDS Parameters table.

EDS Parameters

Parameter # Access Description Parameter Choices Default Setting

Default Value

Data Type

Serial Port Parameters

Serial port character framing

1 Get/Set Defines number of data bits, stop bits, and parity in data character frame.

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

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

8N1 3 USINT

Serial port comm speed

2 Get/Set Defines baud rate of serial port.

0 = 96001 = 12002 = 24003 = 4800

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

9600 baud

0 USINT

Serial port handshaking

3 Get/Set Enables RTS/CTS hardware handshaking on serial port.

0 = RTS/CTS disabled1 = RTS/CTS enabled

Disabled 0 USINT




Default Value

Data Type

Serial Port Receive from ASCII Device

Max number of receive characters

4 Get/Set Max number of characters the module expects to receive into its ASCII port from the serial port.

1…250 20 characters

20 USINT

Receive Record Start mode

5 Get/Set Determines whether start delimiter is included with the received data.

0 = No start delimiter1 = Exclude start delimiter2 = Include start delimiter

No start delimiter

0 USINT

Receive start delimiter

6 Get/Set Character identifies the beginning of the data string from the ASCII device when the length is specified as 0.

Any valid standard ASCII character

(0…127 with 7-bit data)

(0…255 with 8-bit data)

Colon 0x3A USINT

Receive Record End mode

7 Get/Set Selects whether the End delimiter is included with the received data.

0 = No end delimiter1 = Exclude end delimiter2 = Include end delimiter

Include end delimiter

2 USINT

Receive end delimiter

8 Get/Set Character identifies the end of the data string from the ASCII device when the length is specified as 0.

Any valid standard ASCII character(0…127 with 7-bit data)(0…255 with 8-bit data

Carriage return

0Dhex USINT



Receive message time-out

9 Get/Set Number of ms to wait for the next character in the string before defining the current message complete and marking it to produce on the DeviceNet network.

0 = Not active1…65,635 = milliseconds to wait f

Not active 0 USINT

Receive string data type

10 Get/Set Defines the format of the data string sent to the master.

0 = Array1 = Short string2 = String

Short string

1 USINT

Receive Pad mode

11 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

Receive pad character

12 Get/Set The value to use to pad the invalid data portion of the poll response.

Any valid standard ASCII character

Null 0 USINT

Receive Swap mode

13 Get/Set If enabled, the position of the bytes in the serial messages is swapped every 2, 3, or 4 bytes.

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

Disabled 0 USINT


Default Value

Data Type



DeviceNet Handshake mode

14 Get/Set If enabled, master must acknowledge it is ready for next new data before 1799-DASCII module sends the new data.

0 = Master/Slave Handshake1 = Auto Increment (No handshake)

Auto Increment

1 USINT

Gateway produce assembly size

15 Get Total number of I/O data bytes that are sent to the master from the 1799-DASCII module. This should be the RX size of your scanner.

4…254 20 bytes of array data and 4 header bytes

24 USINT

Receive data string

16 Get Serial data in the receive buffer.

Any data string Empty Null USINT

Receive data size

17 Get Number of characters in the Receive data buffer.

0…250 0 0 USINT

Receive record number

18 Get/Set The Receive Record Number sent from the master.

0…255 0 0 USINT


Default Value

Data Type




Default Value

Data Type

Serial Port Receive to ASCII Device

Max number of transmit characters

19 Get/Set Max number of characters the 1799-DASCII module expects to transmit out its serial port to the serial device.

0…250 20 chars 20 USINT

Transmit End Delimiter mode

20 Get/Set Selects whether the End delimiter is included with the received data.

0 = No end delimiter1 = Exclude end delimiter2 = Include end delimiter

Include 2 USINT

Transmit end delimiter character

21 Get/Set Character that identifies the end of the transmit data string from DeviceNet to the ASCII device when the length is specified as 0.

Any valid standard ASCIIcharacter(0…127 with 7-bit data) (0…255 with 8-bit data)

Carriage return

0Dhex USINT




Default Value

Data Type

Gateway Consume on DeviceNet Network from Master

Consume string data type

22 Get/Set Defines the format of the data string received from the master.

0 = Array1 = Short string2 = String

Short string

1 USINT

Transmit Swap mode

23 Get/Set If enabled, the position of the bytes in the serial messages is swapped every 2 or 4 bytes.

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

Disabled 0 USINT

Gateway consume assembly size

24 Get Total number of I/O data bytes that are received from the master. This should be the TX size of your scanner.

4…254 20 bytes of array data and 4 header bytes

24 USINT

Parameter # Access Description Parameter Choices

Default Setting

Default Value

Data Type

Serial Port Transmit/Explicit Messages from EDS Editor

Transmit data string

25 Get/Set Serial data to be sent to the serial transmit buffer.

ASCII block data Empty USINT

Transmit data length

26 Get/Set Length of the Transmit Serial Data.

0…250 0 0 USINT



Configuration Assembly

The 1799-DASCII module supports a configuration assembly as shown below. The configuration assembly is accessed through the Assembly Object (Class 4) Instance 103. The configuration assembly data size is 22 bytes.

Transmit record number

27 Get/Set The record number of the current transmit data buffer.

0…255 0 0 USINT

Status 28 Get The Combined status byte for the Serial Port Object. The Receive Record object and the Transmit Record object.

No status 0 USINT

Autobaud 29 Get/Set DeviceNet Baud Rate

0 = fixed baud rate1 = Enable Autobaud

Enable Autobaud

1 USINT

Byte Parameter Definition EDS Parameter

0 ASCII Serial Character Format 1

1 ASCII Serial Comm Speed 2

2 ASCII Hardware Handshake 3

3 ASCII Max Number of Receive Characters 4

4 ASCII Receive Record Start Mode 5

5 ASCII Receive Start Delimiter 6

6 ASCII Receive Record End Mode 7

7 ASCII Receive End Delimiter 8

8, 9 ASCII Receive Message Timeout 9

10 ASCII Receive String Data Type 10

11 ASCII Receive Pad Mode 11

12 ASCII Receive Pad Character 12

13 ASCII Receive Swap Mode 13

Parameter # Access Description Parameter Choices

Default Setting

Default Value

Data Type



Configuring the ParametersThe 1799 I/O modules have parameters that are configurable through a DeviceNet configuration tool, such as RSNetWorx for DeviceNet software. The DeviceNet configuration tools require an electronic data sheet (EDS) for the 1799 I/O modules to configure the module’s parameters. Find the EDS files at http://www.rockwellautomation.com/support/.

Set Up the Serial LinkParameters 1, 2, and 3 let you define the serial link communication options.

See these parameters in the EDS Parameters table on page 12.

14 DeviceNet Handshake Mode 14

15 ASCII Receive Record Number 18

16 ASCII Max Number of Transmit Characters 19

17 ASCII Transmit End Delimiter Mode 20

18 ASCII Transmit End Delimiter Character 21

19 ASCII Consume String Data Type 22

20 ASCII Transmit Swap Mode 23

21 Autobaud 29

Byte Parameter Definition EDS Parameter


http://www.rockwellautomation.com/support/


Serial Character Framing (parameter 1)

This defines the number of data bits and stop bits used in each character's data frame. It also defines the type of character frame parity used.

Serial Comm Speed (parameter 2)

This defines the baud rate options available on the serial port.

RTS/CTS Hardware Handshaking (parameter 3)

With an RS232 connection, the 1799-DASCII module supports hardware handshaking for data exchange via RTS/CTS control lines on the DB9 connectors. When used with an ASCII device that also supports hardware handshaking, the RTS and CTS lines are used to meter data flow between the module and device and prevent data buffer overflow. This option can be enabled and disabled via software.


Default Value

Data Type

Serial Port Parameters

Serial port character framing

1 Get/Set Defines number of data bits, stop bits, and parity in data character frame.

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

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

8N1 3 USINT

Serial port comm speed

2 Get/Set Defines baud rate of serial port.

0 = 96001 = 12002 = 24003 = 4800

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

9600 baud

0 USINT

Serial port hand-shaking

3 Get/Set Enables RTS/CTS hardware handshaking on serial port.

0 = RTS/CTS disabled1 = RTS/CTS enabled

Disabled 0 USINT



Receive Serial Data from the ASCII DeviceThe 1799-DASCII module receives a number of characters at its serial port and transmits these to the DeviceNet master (produces on the DeviceNet network) via the following:

• Polled I/O• Change-of-state (COS)• Cyclic• Explicit Message

The received character string is captured when one of the following occurs:

• The specific number of bytes defined (max number of Receive characters) is received.• The defined End-of-String Terminator character is detected.• The specified non-zero time-out value (Message Time-out) is reached.

When any of these events occur, the 1799-DASCII module stores the received message string in its internal buffer and transmits (produces) it onto the DeviceNet network at the next opportunity.

Set Up the Receive-character Buffer Length (parameter 4)

The receive character buffer length is the number of characters that the 1799-DASCII module can receive from the serial 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 a 4-byte header.

When the 1799-DASCII module receives the character that fills the buffer, it sets the nondelimited RECORD status flag and forces the data in the receive buffer to be



sent to the master. If the 1799-DASCII module receives a character while the buffer is full, it internally generates an overflow error in the status byte.

The subsequent received characters are received into the buffer and handled as the

start of the next incoming message string.

Set Up and Using Delimiter Operation (parameters 5, 6, 7, 8)

When receiving data strings from the serial device, the 1799-DASCII module can take advantage of Start and Stop (End) delimiters. The Start Delimiter is the start-of-string indicator and the End Delimiter is the end-of-string indicator. This lets explicit control over which characters are sent to the master.

When Start Delimiter operation is selected, a character must be defined that prompts the 1799-DASCII module to start storing the incoming data string. All characters up to this Start Delimiter (after the previous message was completed) are ignored. Once the Start Delimiter is received, all characters are stored until the End Delimiter is received or the Max Receive Char Length is reached (or the RX Time-out time is exceeded, if that option is selected). Once the End Delimiter is reached, the data string is captured and prepared to send to the DeviceNet master.

If either delimiter is used, you can also elect whether to include those characters in the string sent to the master. The Start Delimiter mode parameter is 5, the Delimiter character is 6. The End Delimiter mode is parameter 7 and the End Delimiter character is 8.

Rx Message Time-out (parameter 9)

The 1799-DASCII module has a receive time-out value configurable in 1 ms increments. When this value is non-zero, the module's timeout counter resets on the receipt of each new byte of data. If the timeout counter expires, the module sets the nondelimited flag in the Status Byte and updates the Produce buffer with the current data string.

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

This value can be set and retrieved by EDS parameter 4.

Message Time-out Values

Value Time-out Action

0 Disabled

1…65,535 Time-out time in milliseconds (ms)



Produce Received-serial Data onto DeviceNet Network

Received-string Data Type (parameter 10)

The format of the data is Array, Short_String, or String - sent to the DeviceNet master, as shown below. Choose the one best suited for your application and that modifies the format of the data field.

The format of the data sent to the 1799-DASCII module is Array, Short_String, or String. Choose the one best suited for your application and modifies the format of the data field.

The Array data type has no length associated with it. It is equivalent to specifying a length of zero by using a string or short_string data type.

The Short_String data type is the default data type of the device. This suffices for most applications. The Short_String data type has only 1 byte of length, and the rest of the data bytes are appended after the length.

The String data type has 2 bytes of length. The String data type is useful in talking to programmable controllers or other devices that have a data file specifically made to handle this data type. The length is Little Endian (low byte, high byte), and the high order byte should be set to zero. The 1799-DASCII module only receives up to 250 bytes of information, so the extra byte, although required for this data type, is 0.

Received-string Data DeviceNet Assembly Formats

The following tables define the format that the 1799-DASCII module produces on DeviceNet network and sends to the DeviceNet master. In all cases, the size of the assembly is equal to the length of the received ASCII string plus a 4-byte header.

IMPORTANT If the Short_String or String data type is used, the length is not sent to the ASCII device.

Produce Data DeviceNet Format - Array String Type

Byte 1 Byte 2 Byte 3 Byte 4 Byte 5-X (250 bytes max)

Transaction ID Status byte Reserved Reserved ASCII data (including optional <terminator>.



Set Up and Use Pad Mode (parameters 11 and 12)Pad mode operation is the method used by the 1799-DASCII module to add 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 a constant length, and that length is the number specified in the Receive Character Length parameter, plus any header options. The quantity of pad characters sent can vary from message to message, depending on the size of the incoming string.

Pad Mode Selection (parameter 11)

Pad mode is included for compatibility with scanners that cannot receive variable length I/O messages. For such scanners, you must turn on Pad mode (a value of 1). Turning Pad mode on does not harm scanners that do support variable length receive messages. The default value for Pad mode is off. If the scanner does support variable I/O messaging lengths, the Pad mode option can be set to off (a value of 0) to conserve some network bandwidth.

The selection of Pad mode is valid only for the DeviceNet message that the 1799-DASCII produces. It has no effect on DeviceNet messages sent from the scanner to the 1799-DASCII module. This value can be set and retrieved by using the standard set and get services on Use parameter 11 of Table 4.

Pad Mode Character (parameter 12)

You can 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). This value can be set and retrieved by using the standard set/get services on parameter 12. See the EDS Parameters table starting on page 12.

Produce Data DeviceNet Format - String_String Type


Transaction ID Status byte Reserved Length ASCII data (including optional <terminator>.

Produce Data DeviceNet Format - String String Type


Transaction ID Status byte Length (low byte) Length (high byte) ASCII data (including optional <terminator>.



Set Up and Use the Swap Bytes Mode (parameter 13)This option may be helpful if the 1799-DASCII module is connected to a DeviceNet scanner that organizes the data string characters into data type elements that are larger than 1 byte each. An example is the Allen-Bradley SLC 500 module. In such cases, the bytes of the data in the master's memory organization can be reversed from the order in which they are sent or received on the DeviceNet network and the serial link to the ASCII device. This may cause anomalies in some cases.

The message received or desired "ABCDEFGH" string may appear in memory as "BADCFEHG" for 2-byte word organization, and "DCBAHGFE" for 4-byte word organization.

Transmit Byte Swapping

By setting parameter 23, the bytes from the master are swapped by the 1799-DASCII module before transmitting the string to the ASCII device.

Rules for Usage

The rules for usage are the following:

• This feature is set for transmit and receive independently.• Byte swapping works better if the string length is an even multiple of the byte-swap size.• If a delimiter is received, then all characters up to and including the defined delimiter are sent to the

DeviceNet master.

If Pad mode = 1, then the 1799-DASCII module fills the Poll Response data with the Pad Char up to the defined size.

If Pad mode = 0, then the 1799-DASCII module sends only the data up to and including the delimiter.

• If no delimiter is received, then the 1799-DASCII module receives up to Max_Number_of_Receive_Chars, and sends this string to the DeviceNet network with an overflow error.

It continues to receive and send strings of size Max_Number_of_Receive_Chars, along with the overflow error, until a delimiter is received. This could continue indefinitely if the I/O device does not transmit the specified delimiter.

Master-Slave Handshake versus Immediate Mode (parameter 14)

If DeviceNet Master-Slave Handshake mode is selected, the DeviceNet master can inhibit the 1799-DASCII module from sending new ASCII data until the master is ready to receive and process the new data.



In this mode the two required for the complete transaction are the following: • A "New Data Available" flag is set by the 1799-DASCII module in the status byte. This informs the

master that the 1799-DASCII module has received a new data string and is waiting for the OK to send it.

• The first byte of the message the master sends to the 1799-DASCII module is the RX ID Record. By setting the value of this byte to the value of the new record number pending, it indicates to the 1799-DASCII module that the master is ready to receive the new data.

The master monitors this new data flag and when the master is ready to receive new serial data, it sets a new number in the new record number byte of the next poll command message. This applies only to data being sent from the 1799-DASCII module to the master.

The operation proceeds as follows.

1. The 1799-DASCII module receives a new data string.

2. The 1799-DASCII module sets the New Data flag in the Status byte of its next produce message.

3. The master sends out messages to the 1799-DASCII module in the normal fashion. If the master is not ready to receive new data, the New Record Data byte remains set.

4. When the master is ready to receive the new data string, it changes the New Record Data byte to any value different than what it had been sending.

5. The 1799-DASCII module sends the new data upon receipt of a record from the master in which the New Record Data byte has been changed.

6. If the 1799-DASCII module receives an updated New Record Data byte and has no new data, it sets the Handshake Error bit in its Produce Status byte.

In Immediate mode, this handshaking is not active and the 1799-DASCII module sends new data as soon as it is received from the ASCII device with the new Transaction ID. It is the master's responsibility to be ready to accept and process the new data string when it is presented.

Identify the Scanner I/O Receive Size (parameter 15)

The 1799-DASCII module automatically calculates the number of bytes it sends the DeviceNet master. Its value is determined by a combination of the incoming data and the options you selected. Parameter 15 is a read-only value that defines the size of the DeviceNet message to be sent by the 1799-DASCII module to the master.



Explicit Messages to Receive the Serial Data String (parameters 16, 17, 18)

Parameters 16, 17, and 18 contain the status of the most-recent incoming serial data string. You can use the data to read the device's ASCII data via the Explicit Messaging technique.

Parameter 16 holds the most recent received data.

Parameter 17 defines the size, in bytes, of the DeviceNet message to be sent by the 1799-DASCII module to the master.

Parameter 18 holds the record number of the data string in parameter 16 if the Header option is selected.

Serial Status Byte Description and TransmissionThe Serial Status byte is an OR'd bitfield of a number of status and exceptions flags.

IMPORTANT If you are using a scanner that must receive a constant message length, set its Rx (receive) value to this number of bytes.

Serial Status Byte

Bit Exception Description

0 Tx I/O 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 I/O, this bit resets.

1 Rx I/O overflow

The receive queue has overflowed resulting in a loss of data. The receive I/O is full of data waiting to be processed. A new character arrives before the buffer is emptied, thus setting the overflow bit. The data character is lost. When space becomes available in the RX I/O, this bit resets.

2 Rx parity error The message has a parity error. One or more of the characters has a parity error.

3 Rx overrun error

A byte that has not been read has been overwritten by another received byte, resulting in data loss.

4 Rx framing error

When the stop bit of a received character is a logic zero, a framing error occurs.



Concerning transmitting serial data to an ASCII device, the 1799-DASCII module transmits character strings to the serial device that it has received from the DeviceNet master via the following:

• Poll I/O • Explicit Message

The character string is transmitted when either of the following conditions occurs in the data within the DeviceNet message data field:

• The specific number of bytes defined (Transmit Character Buffer Length) is received.• The defined End-of-String Terminator character is detected.

When either of these events occurs, the 1799-DASCII module stores the DeviceNet string data into its internal buffer and transmits it out its serial port.

To transmit data to the serial device, the data must first be sent to the 1799-DASCII module and then the 1799-DASCII module must send the data to the serial device. The set-up for transmitting from the master to the 1799-DASCII module are discussed first.

Consume Data Assembly Formats from DeviceNet MasterThe assembly format options of the data to be sent from the DeviceNet master to the 1799-DASCII module are shown below. The one selected depends on the application. Refer to Transmit String Data Type Formats (parameter 22).

5 Nondelimited string

The current message has filled the buffer without a termination character, and is being transmitted in total. This is not an error. It is caused by characters filling, but not overflowing the receive buffer. This causes the 1799-DASCII module to transmit the characters to the master.

6 Handshake error

This error occurs in Master-Slave Handshake mode. It indicates that the master has requested a new data record from the 1799-DASCII module, but the 1799-DASCII module has not indicated new data is available to be sent.

7 New data flag This bit is used only when the Master-Slave Handshake option is active. When the 1799-DASCII module receives a new data string into its serial port, it sets this flag in its DeviceNet response message. The bit remains set for 1 produce message after the master requests the new data. It resets.

Consume Data DeviceNet Format - Array Data Type


Rx ID Byte (Handshake mode only)

Transaction ID Byte

Reserved Reserved ASCII data (including optional <terminator>.

Serial Status Byte

Bit Exception Description



Transmit String Data Type Formats (parameter 22)

This is the format of the data sent from the 1799-DASCII module - array, short_string, or string - to the DeviceNet master. These are shown in the following sections. Which one you pick depends on the application and modifies the format of the data field. To change the string format, use parameter 22.

Set Up and Use the TX Byte Swap Mode (parameter 23)

This option is helpful if the 1799-DASCII module is connected to a DeviceNet scanner that organizes the data string characters into data type elements that are larger than 1 byte each. An example is an Allen-Bradley PLC, such as the SLC 500 controller. In such cases, the bytes of the data in the master's memory organization can be reversed from the order in which they are sent or received on the DeviceNet network and the serial link to the ASCII device. This may cause anomalies in some cases.

Identify Scanner I/O Transmit Size (parameter 24)

The 1799-DASCII module automatically calculates the number of bytes it expects from the DeviceNet master. Its value is determined by a combination of the incoming data and the options selected. Parameter 24 is a read-only value that defines the size of the DeviceNet message sent to the 1799-DASCII module from the master.

Consume Data DeviceNet Format - Short_String Data Type



Transaction ID Byte

Reserved Length ASCII data (including optional <terminator>.

Consume Data DeviceNet Assembly Format - String Data Type

Byte 1 Byte 2 Byte 3 Byte 4 Byte 5-X (max 128 bytes)


Transaction ID Byte

Length (low byte) Length (high byte) ASCII data (including optional <terminator>.

IMPORTANT Set the scanner’s produce size value to this number of bytes.



Transmit Serial Data to the ASCII Device Read this section for information about transmitting serial data to the ASCII device.

Set Up the Transmit-character Buffer Length (parameter 19)

The Transmit-character buffer length is the number of characters that the 1799-DASCII module can receive in its transmit buffer from the DeviceNet system. This size contributes to the I/O's Consume Size. This size can be found in the Parameter object.

Set Up and Use the Transmit Delimiter (parameters 20 and 21)

The transmit delimiter is an end-of-string character that is used by the 1799-DASCII module to determine how many bytes to transmit over the serial link to the 1799-DASCII device. This transmit delimiter is used if the Transmit Buffer Length equals 0. If the buffer length is not 0, the 1799-DASCII module ignores the transmit delimiter.

The 1799-DASCII module transmits up to and including the delimiter when the above condition is met. The transmit delimiter can be set to any valid I/O character that can be received over the link (parameter 21). Be careful not to set the delimiter to a value outside of the valid range for the number of data bits. (Note that a data bit size setting of 7 lets a delimiter range of 0…127 dec., 00…7Fhex). If the delimiter is not valid, or the delimiter is never received, the device updates the output buffer on detection of a buffer filled condition. These values can be set and retrieved by using the standard set/get services in the Transmit Record Class 0x71.



Transmitting Serial Data

The length of the string set determines the use of a delimiter in transmitting data to a serial device from the 1799-DASCII module.

If the string length is zero, or the data type is type Array, the following happens:• The 1799-DASCII module receives data sent from the DeviceNet master and uses the End Delimiter to

determine how much data is sent to the serial device. The 1799-DASCII module computes the length and stores this as the new length in the string attribute. (This does not appear if the data type is array. You see the string truncated and the length is in the background.)

• If a delimiter is contained within the string, all characters in the data field up to and including the defined delimiter are stored.

• If no delimiter is contained within the string, the 1799-DASCII module stores the data in the data field received.

If the string length > 0 or the data type is String or Short_String, the following happens:

• The 1799-DASCII receives data sent from the DeviceNet master, ignoring any embedded terminator. It stores the number of characters defined in Max_Number_of_Transmit_Chars, or the total sent by the master, whichever is less.

Now, the 1799-DASCII sends the data immediately if attribute X is set to 1. You can cause this data to be transmitted by incrementing the record counter.

The following identifies which parameters transmit serial data to the ASCII device: • Explicit Messages to Transmit Serial Data String• Parameters 26, 27, and 28 can be used to set up the serial data string and send it to the ASCII device

via the Explicit Messaging technique• Parameter 26 holds the data to be sent • Parameter 27 defines the size, in bytes, of the DeviceNet message to be sent from the 1799-DASCII

module to the device • Parameter 28 holds the record number of the data string in parameter 24 if the Header option is

selected. Changing the record causes the data in parameter 24 to be transmitted immediately from the master to the 1799-DASCII module



Status IndicatorsThe 1799-DASCII module has two indicators that provide visual status information about the module and the DeviceNet network. Refer to the Module Status and Network Status tables to interpret the status indications.

The 1799-DASCII module has two RS-232 activity indicators: one for transmit (TX) and one for receive (RX). Each of these indicators illuminates when data communication is active on the respective data lines.

Module Status Indicator (labeled MS)

Indicator Module Status Description

Off No power There is no power through the DeviceNet network.

Solid green Device operational 1799-DASCII module is operating normally.

Flashing green Device in standby 1799-DASCII module needs commissioning (for example, attempting autobaud).

Flashing red Minor fault Recoverable fault.

Solid red Unrecoverable fault Replace 1799-DASCII module.

Flashing red/green Device self-testing 1799-DASCII is in self-test mode.

Network Status Indicator (labeled NS)

Indicator Network Status Description

Off No power or not online 1799-DASCII module has no power, has not completed the Dup_MAC_ID test, or needs commissioning.

Solid green Online, connected 1799-DASCII module operating correctly.

Flashing green Online, not connected 1799-DASCII module is online but is not allocated to a master.

Flashing red Connection time-out One or more I/O connections are timed out.

Solid red Critical link failure 1799-DASCII module detected an error that makes it incapable of communicating on the link (bus off or duplicate MAC ID).

Serial Port Indicator (labeled TX and RX)

Indicator Serial Port Status Description

Off No data communication active 1799-DASCII module has no active data communication on the data line.

On Data communication active 1799-DASCII module has active data communication on the data line.



Specifications

DeviceNet Serial Interface Module- 1799-DASCII

Attribute Value

Description Communication gateway between a serial-capable device over an RS-232 or RS-485 interface and a DeviceNet network

Device type Rockwell Miscellaneous, 115, 0x73 hex

Product code 220, 0xDChex

Vendor ID Allen-Bradley/Rockwell Automation

Device profile Identity Object 0x01Message Router Object 0x02DeviceNet Object 0x03Assembly Object 0x04Connection Object 0x05Parameter Object 0x0FAcknowledge Handler 0x2BSerial I/O Object 112, 0x70 (vendor-specific)Transmit Serial Object 113, 0x71 (vendor-specific)Receive Serial Object 114, 0x72 (vendor-specific)

Product revision 1.01

DeviceNet Baud rate: autobaud operation and software selectionAddress selection: address number 0…63 with rotary switchesDeviceNet connection: 5-pin open connector

Serial port RS-232 and RS-485Baud rate: 1200, 2400, 4800, 9600, 19.2 k, 38.4 k, 57.6 k, 115.2 kParity: odd/even/noneConnector: - pin D-shell, 9-pin male D-shell

Indicators DeviceNet network:Module status - red/greenNetwork status - red/green Serial port:Transmit active - greenReceive active - green

Isolation voltage 50V (continuous), Basic Insulation TypeType tested at 1500V DC for 60 s, DeviceNet network to Serial, and Logic to Communication ports

Power 1.8 W: 75 mA @ 24V DC max

Enclosure type rating None (open-style)

Weight, approx. 34.6 g (1.22 oz)



Environmental Specifications

Attribute Value

Temperature, operating IEC 60068-2-1 (Test Ad, Operating Cold),IEC 60068-2-2 (Test Bd, Operating Dry Heat),IEC 60068-2-14 (Test Nb, Operating Thermal Shock):-20…70 °C (-4…158 °F)

Temperature, nonoperating IEC 60068-2-1 (Test Ab, Unpackaged Nonoperating Cold),IEC 60068-2-2 (Test Bb, U npackaged Nonoperating Dry Heat),IEC 60068-2-14 (Test Na, Unpackaged Nonoperating Thermal Shock): -40…85 °C (-40…185 °F)

Relative humidity IEC 60068-2-30 (Test Db, Unpackaged Nonoperating Damp Heat): 5…95% noncondensing

Shock, operating IEC 60068-2-27 (Test Ea, Unpackaged Shock)30 g peak acceleration

Shock, nonoperating IEC 60068-2-27 (Test Ea, Unpackaged Shock)50 g peak acceleration

Vibration IEC 60068-2-6 (Test Fc, Operating)5 g @ 10…500 Hz

ESD immunity IEC 61000-4-2:8 kV indirect contact discharges

Radiated RF immunity IEC 61000-4-3:10V/m with 1 kHz sine-wave 80%AM from 30…2000 MHz10V/m with 200 Hz 50% Pulse 100%AM at 900 MHz10V/m with 200 Hz 50% Pulse 100%AM at 1890 MHz3V/m with 1 kHz sine-wave 80%AM from 2000…2700 MHz

EFT/B immunity IEC 61000-4-4:+2 kV at 5 kHz on communication ports

Surge transient immunity IEC 61000-4-5:+2 kV line-earth (CM) on shielded ports

Conducted RF immunity IEC 61000-4-6:10V rms with 1 kHz sine-wave 80% AM from 150 kHz…80 MHz

Emissions CISPR 11Group 1, Class A

Wire Size 0.25...2.5 mm2 (22...14 AWG) solid or stranded shielded copper wire rated at 80 °C (176 °F) or higher. Refer to DeviceNet Media Design And Installation Guide, publication DNET-UM072.

Wiring category(1) 2 - on communication ports

(1) Use this Conductor Category information for planning conductor routing. Refer to Industrial Automation Wiring and Grounding Guidelines, publication 1770-4.1.



Certifications

Certification(1) Value

c-UL-us UL Recognized Component Industrial Control Equipment, certified for US and Canada. See UL File E65584.

CE European Union 2004/108/EC EMC Directive, compliant with:EN 61326-1; Meas./Control/Lab., Industrial RequirementsEN 61000-6-2; Industrial ImmunityEN 61000-6-4; Industrial EmissionsEN 61131-2; Programmable Controllers (Clause 8, Zone A & B)

C-Tick Australian Radiocommunications Act compliant with AS/NZS CISPR 11, Industrial Emissions

ODVA ODVA conformance tested to DeviceNet specifications

(1) See the Product Certification link at http:// www.ab.com for Declaration of Conformity, Certificates, and other certification details.


http://www.ab.com

Rockwell Automation Support

Publication 1799-IN012B-EN-P - July 2008 PN-29563Supersedes Publication 1799-IN012A-EN-P - November 2007 Copyright © 2008 Rockwell Automation, Inc. All rights reserved. Printed in the U.S.A.

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For an additional level of technical phone support for installation, configuration and troubleshooting, we offer TechConnect support programs. For more information, contact your local distributor or Rockwell Automation representative, or visit http://support.rockwellautomation.com.

Installation AssistanceIf you experience a problem within the first 24 hours of installation, please review the information that's contained in this manual. You can also contact a special Customer Support number for initial help in getting your product up and running.

New Product Satisfaction ReturnRockwell Automation tests all of its products to ensure that they are fully operational when shipped from the manufacturing facility. However, if your product is not functioning and needs to be returned, follow these procedures.

Allen-Bradley, Rockwell Automation, RSNetWorx for DeviceNet, SLC 500, and TechConnect are trademarks of Rockwell Automation, Inc.

Trademarks not belonging to Rockwell Automation are property of their respective companies.

United States 1.440.646.3434Monday – Friday, 8 a.m. – 5 p.m. EST

Outside United States

Please contact your local Rockwell Automation representative for any technical support issues.

United States Contact your distributor. You must provide a Customer Support case number (see phone number above to obtain one) to your distributor in order to complete the return process.

Outside United States

Please contact your local Rockwell Automation representative for the return procedure.

http://support.rockwellautomation.com

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Documents

DeviceNet Serial Interface Module...6 DeviceNet Serial Interface Module Publication 1799-IN012B-EN-P - July 2008 To reset the node address, use a screwdriver to rotate the switches