ICPDAS GW-7553-B, GW-7553-M User Manual

GW-7553-B / GW-7553-M PROFIBUS/Modbus TCP Gateway User Manual (Version 1.35, May/2017)
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GW-7553-B / GW-7553-M PROFIBUS/Modbus TCP Gateway

User's Manual

High Quality, Industrial Data Acquisition, and Control Products

Warranty

All products manufactured by ICP DAS are under warranty regarding
defective materials for a period of one year from the date of delivery to the
original purchaser.

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Warning

ICP DAS assumes no liability for damages resulting from the use of this
product. ICP DAS reserves the right to change this manual at any time
without notice. The information furnished by ICP DAS is believed to be
accurate and reliable. However, no responsibility is assumed by ICP DAS
for its use, or for any infringements of patents or other right of third parties
resulting from its use.

Copyright

Copyright 2013 by ICP DAS. All rights are reserved.

Trademark

The names used for identification only may be registered trademarks of
their respective companies.

List of Revision

Date

Author

Version

Revision

2012/05/10

Ryan

1.33

Release

2013/05/30

Elliot

1.34

Release

2017/05/15

Eric

1.35

Add GW-7553-M
information.

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Table of Contents

1. Introduction 4

1.1 Features 5

1.2 Modules Support 5

1.3 Specification 5

2. Hardware 7

2.1 Block Diagram of GW-7553-B / GW-7553-M 7

2.2 Pin Assignment 7

2.3 Wiring 9

2.4 Setting the PROFIBUS Address 12

2.5 LED status indicator 14

2.6 Normal/Setting DIP switch 15

3. Communication protocol transfer theorem 17

3.1 PROFIBUS data exchange 17

3.2 Modbus data exchange 20

3.3 Communication protocol transfer 23

3.4 PROFIBUS DP-V1 Acyclic Service 28

4. Communication 32

4.1 Field of application 32

4.2 GSD file 33

4.3 The Configuration of the common parameters 35

4.4 The Configuration of the modules 38

4.5 Diagnostic messages 40

4.6 I/O data exchange 42

4.7 Establish connection with GW-7553-B / GW-7553-M 45

4.8 Data exchange example—Modbus RTU 46

4.9 Data exchange example—Modbus TCP 56

5. Application of Utility 93

5.1 Install Utility 93

5.2 Utility introduction 96

5.3 Memory address configuration of the module 98

5.4 Safe value setting 101

5.5 IP setting 103

5.6 Establish connection with GW-7553-B / GW-7553-M 104

6. Configuration with Web Browser 108

6.1 Connecting to Web Server 108

6.2 Web Configuration—Function menu 109

6.3 Web Configuration—Setup page 110

7. Troubleshooting 118

8. Dimensions 120

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1. Introduction

PROFIBUS and Modbus are two kinds of famous protocols and are wildly used in
the fields of factory and process automation. The GW-7553-B / GW-7553-M is a
PROFIBUS to Modbus TCP gateway. By using this module, users can easily put the
Modbus TCP devices into PROFIBUS network.

Figure 1 shows an application example for the GW-7553-B / GW-7553-M module.

Figure 1 Application architecture of the GW -7553-B / GW-7553-M module

The GW-7553-B / GW-7553-M Gateway is specially designed for the slave device of
PROFIBUS DP protocol. In the Modbus protocol application, the GW-7553-B / GW­7553-M can be a Modbus Master device or Slave device. The Modbus devices can
exchange data with the PROFIBUS Master device via the GW-7553-B / GW-7553-M
module.

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The main features and specification of GW-7553-B / GW-7553-M are described as
below:

1.1 Features

● 16-bit Microprocessor inside with 80MHz

● Profichip VPC3+C PROFIBUS controller

● Support PROFIBUS DP-V0 & DP-V1 slave

● PROFIBUS transmission rate detect automatically

● Max transmission speed up to 12 Mbps for PROFIBUS and 115.2 kbps for

COM Port

● Support Modbus RTU, ASCII and TCP format

● Support Modbus Master/Slave mode

● Support safe value setting

● COM Port driver has 1K bytes QUEUE input buffer & 512 bytes QUEUE

output buffer

● Max length of output/input data is 240/240 Bytes

● Ethernet Port: 10/100 Base-TX

● 2500Vrms High Speed iCoupler Isolation Protection for PROFIBUS network

● 3000VDC Isolation Protection on the PROFIBUS side

● Provide LED indicators

● Built-in Watchdog

● Mountable on DIN Rail

1.2 Modules Support

Only the following Modbus commands are supported by the gateway.

Table 1 Modbus function codes

Code

Name

Description

01

Read Coil Status

Read the ON/OFF status of discrete outputs in the slave

02

Read Input Status

Read the ON/OFF status of discrete inputs in the slave

03

Read Holding Registers

Read the binary contents of holding registers in the slave

04

Read Input Registers

Read the binary contents of input registers in the slave

05

Force Single Coil

Write a single output to either ON or OFF in the slave

06

Preset Single Register

Write an integer value into a single register in the slave

15

Force Multi. Coils

Write each coil in the sequence of coils to either ON or
OFF in the slave

16

Preset Multi. Registers

Write a block of contiguous registers in the slave

1.3 Specification

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COM Port specs:

● Serial port - RS-232

● Serial port interface: screw terminal block

● Baud Rate：2400/4800/9600/19200/38400/57600/115200 bps

● Data Format: 7/8 data bits, None/Odd/Even parity bit, 1/2 stop bit

PROFIBUS specs:

● PROFIBUS interface connector: D-Sub 9-pin female

● Baud Rate: 9.6k/19.2k/45.45k/93.75k/187.5k/500k/1.5M/3M/6M/12Mbps

● Address Setting: 0~126 (set by DIP switch or EEPROM)

Ethernet specs:

● 10/100Base-TX (Auto-negotiating, Auto_MDIX, LED indicator)

Power requirement:

● Unregulated +10 ~ +30 VDC

● Power reverse protection, Over-Voltage brown-out protection

● Power consumption 2.5W

Module specs:

● Dimensions:

GW-7553-B : 119mm X 72mm X 33 mm
GW-7553-M :118mm X 102mm X 27 mm

● Operating temperature: -25 ~ 75 ºC

● Storage temperature: -30 ~ 85 ºC

● Humidity：5 ~ 95% RH, non-condensing

● LED Status Indicators(Table 2)

Table 2 LED status indicator

PWR LED

 Show the power state

 Show data state

ERR LED

 Show error state

RUN LED

 Show communication state of PROFIBUS

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2. Hardware

2.1 Block Diagram of GW-7553-B / GW-7553-M

Figure 2 Block diagram of GW-7553-B / GW-7553-M

2.2 Pin Assignment

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Figure 3 Pin assignment of GW-7553-B / GW-7553-M

Table 3 9-pin screw terminal block

Pin

Name

Description

1

CTS

Clear to Send of RS-232

2

RTS

Request to Send of RS-232

3

RX

Receive Data of RS-232

4

TX

Transmit Data of RS-232

5

GND

GND of RS-232

6

-

N/A 7 -

N/A 8 +VS

V+ of Power Supply(+10 ~ +30 VDC)

9

GND

GND of Power Supply

Table 4 RJ-45 socket

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Table 5 PROFIBUS DB9 Female Connector

Pin

Name

Description

1

-

N/A

2

-

N/A

3

B

Non-inverting Bus Line

4

ISODE

Isolated DE output for use in PROFIBUS
applications where the state of the isolated drive
enable node needs to be monitored.

5

GND

Power supply ground for the first node and the last
node

6

VP

+5V Power Supply for the first node and the last
node 7 -

N/A 8 A

Inverting Bus Line

9

-

N/A

2.3 Wiring

GW-7553-B / GW-7553-M supports PROFIBUS to Serial or Ethernet
communication. It is recommended to use only one communication interface (RS­232 or Ethernet) of the Gateway at the same time. The following section describes
the connection interface of GW-7553-B / GW-7553-M.

2.3.1 RS-232 connection

Pin

Name

Description

1

TX+

TX+ output

2

TX-

TX- output

3

RX+

RX+ input 4 -

N/A 5 -

N/A 6 RX-

RX- input 7 -

N/A 8 -

N/A

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The RS-232 port of the GW-7553-B / GW-7553-M has got three pins. The
wiring of the RS-232 device with the RS-232 port of the GW-7553-B / GW­7553-M is shown in Figure 4.

Figure 4 RS-232 wiring diagram

2.3.2 Ethernet connection

The user can connect GW-7553-B / GW-7553-M with the other device to the
same sub network or same Ethernet Switch, as shown in Figure 5.

Figure 5 Ethernet connection

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2.3.3 PROFIBUS Connection

The PROFIBUS interface of the GW-7553-B / GW-7553-M is a DB9 female
connector. The connector uses the standard PROFIBUS 9 pin assignment. It is
recommended to use a standard PROFIBUS cable and connector (DB9 male).
As with every serial bus the rate of safe data transmission in a PROFIBUS
network decreases with increasing distance between Master and Slave. Table 6
shows the transmission rate and range for a cable with the following properties:

1. Impedance :135~165 Ω

2. Capacity : lower than 30 pF/m

3. Loop resistance : lower than 110 Ω/km

4. Wire diameter : greater than 0.65 mm

5. Core cross-section : greater than 0.34 mm2

Table 6 Transmission rate decreasing with increasing transmission distance

Transmission Rate(kbps)

Transmission Distance per Segment (meter)

9.6, 19.2, 45.45,93.75

1200

187.5

1000

500

400

1500

200

3000, 6000, 12000

100

In order to minimize the reflection effect of signal transmission, both ends (first
node and last node) of a PROFIBUS segment needs to be equipped with an
active terminal resistor as shown in Figure 6. A standard PROFIBUS connector
is usually already equipped with a terminal resistor. The user therefore only has
to switch on the resistor of the devices stationed at the ends of a segment as
shown in Figure 7.

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Figure 6 PROFIBUS connection

Figure 7 PROFIBUS connector

The number of stations in a PROFIBUS network is restricted to 126. According
to the PROFIBUS specification up to 32 stations are allowed per segment. A
repeater has to be used to link the bus segments.

2.4 Setting the PROFIBUS Address

The station address of GW-7553-B / GW-7553-M can be set by using either the

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DIP switch or by writing it directly to the EEPROM. The DIP switch covers a
range from 0 to 255. The valid address range of a PROFIBUS station spans from 0
to 126. Table 7 shows three examples of setting the station address by using the
DIP switch. The DIP switches are accessed by opening the modules housing
(Figure 8). Table 8 explains which address will be used by the module after
power on, if the DIP switch address setting differs from the address stored in the
EEPROM.

Table 7 DIP switch setting example

Station address

DIP switch (SW1)

1 2 3 4 5 6 7

8 1 1 0 0 0 0 0 0

0

10

0 1 0 1 0 0 0 0 126

0 1 1 1 1 1 1

0

Note: 1=>ON, 0=>OFF

Table 8 The Address setting of the GW-7553-B / GW-7553-M

DIP switch Setting

Description

0~125

1. The address setting of the EEPROM is ignored.

2. The address can not be set by the PROFIBUS configuration

tool.

126-254

1. The address setting of the DIP switch is ignored.

2. If the address in the EEPROM is 126, the PROFIBUS

configuration tool can set a new address and save it to the
EEPROM.

255

1. Slave address in the EEPROM is set to 126.

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Figure 8 DIP switch

Each Slave must have a unique valid address (1 to 125) in order to be able to
communicate with the Master. To change the address by using the configuration
tool it is necessary to first set the address stored in the EEPROM to 126. This is
done by setting the DIP switch to 255 in the power off state. Switching the
module on is forcing the module to change its address in the EEROM to 126. In
the next step switch the module off and change the DIP switch setting to any
value from 126 to 254. This step is necessary in order to prevent the module to
change its address in the EEPROM to 126 every time it is powered on. The
configuration tool can now assign the Slave a new address.

2.5 LED status indicator

The GW-7553-B / GW-7553-M provides three LEDs to indicate the statuses of
the GW-7553-B / GW-7553-M module. The position of LEDs and descriptions
are shown in Table 9 and Figure 9.

Table 9 LED status description

LED Name

Status

Description

PWR

flash

When the GW-7553-B / GW-7553-M acts as a
Modbus Slave device and receiving query message
form Modbus Master device, PWR led will flash.

on

Power supply is ok.
The firmware has loaded.

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LED Name

Status

Description

off

Power supply has failed.

ERR

flash

When the GW-7553-B / GW-7553-M connects with
the utility tool, it will flash fast (flash once about
55ms).
When the GW-7553-B / GW-7553-M has diagnostic
message, it will flash slowly (flash once about 220ms).

on

 Connection error between PROFIBUS Master and

Slave or

 PROFIBUS system has not been configured

correctly.

off

Normal operation
PROFIBUS system has been configured correctly

RUN

on

Data exchange mode
Normal operation.

off

GW-7553-B / GW-7553-M module is not in a data
exchange mode.

Figure 9 LED position

2.6 Normal/Setting DIP switch

There is a DIP switch on the back of the GW-7553-B module, as shown in Figure 10.

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The DIP switch is used to set the GW-7553-B module works in operation mode or
setting mode. In the normal situation, it needs to set the DIP switch to the “Normal”
position. In this case, the GW-7553-B module can communicate with Modbus devices.
When the user sets the DIP switch to the “Setting” position, the GW-7553-B module
can communicate with the utility to set the safe value and network configuration.

GW-7553-M module only can connect to Utility via setting the control bit (please
refer section 4.6.2 Output data area and communication command) to enable the
setting mode of the GW-7553-M.

Figure 10 DIP switch of the GW-7553-B

PS:

There are two kinds of methods to enable the setting mode of the GW-7553-B.
The user can change the position of the DIP switch or set the control bit (please refer
section 4.6.2 Output data area and communication command) to enable the setting
mode of the GW-7553-B, as shown in Table 10 .

Table 10 Mode of GW-7553-B

Mode

SM(control bit)=0

SM(control bit)=1

DIP switch=Normal

operation mode

setting mode

DIP switch =Setting

setting mode

setting mode

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3. Communication protocol transfer theorem

3.1 PROFIBUS data exchange

The GW-7553-B / GW-7553-M is a PROFIBUS DP Slave device. The GW-7553­B / GW-7553-M is first parameterized then configured and finally it goes into the
data exchange mode (Figure 11).

Figure 11 State machine of PROFIBUS DP Slave device

The GW-7553-B / GW-7553-M exchanges data cyclically between internal DI、
DO、AI、AO data and PROFIBUS Master device in data exchange mode, as
shown in Figure 12.

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Figure 12 Data exchange between PROFIBUS Master device and GW-7553-B /
GW-7553-M

The GW-7553-B / GW-7553-M downloads the parameter and configuration from
PROFIBUS Master device to be the module parameters. The GW-7553-B / GW­7553-M and PROFIBUS Master device have different data type and data address,
the GW-7553-B / GW-7553-M can transfer different data format to PROFIBUS
Master device through module parameters. When the GW-7553-B / GW-7553-M
acts as a Modbus Master device, it will send DI、AI data to input data area of

PROFIBUS Master device and it will save data that receives from PROFIBUS
Master device to internal DO、AO memory space, as shown in Figure 13

、

Figure 14.

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Figure 13 The output data of PROFIBUS Master device send to the GW-7553-B /
GW-7553-M

Figure 14 The input data of PROFIBUS Master device receive from the GW-7553-B /
GW-7553-M

When the GW-7553-B / GW-7553-M acts as a Modbus Slave device, it will send
DO、AO data to input data area of PROFIBUS Master device and it will save data

that receives from PROFIBUS Master device to internal DI、AI memory space, as
shown in Figure 15、Figure 16.

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Figure 15 The output data of PROFIBUS Master device send to the GW-7553-B /
GW-7553-M

Figure 16 The input data of PROFIBUS Master device receive from the GW-7553­B / GW-7553-M

3.2 Modbus data exchange

Modbus protocol belongs to Master-Slave communication and it uses query and
response message to arrive at data exchange and device control, as shown in

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Figure 17 Data exchange between the Modbus devices and the GW-7553-B / GW-7553-M.

Figure 17 Data exchange between the Modbus devices and the GW-7553-B / GW­7553-M

When the GW-7553-B / GW-7553-M acts as a Modbus Master device, it can get
query message through module parameter and DO、AO data and send query

message to Modbus Slave device. It can also receive response message form
Modbus Slave device and then saving to internal DI、AI memory space, as

shown in Figure 18、Figure 19.

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Figure 18 GW-7553-B / GW-7553-M output data to Modbus Slave devices

Figure 19 GW-7553-B / GW-7553-M receive data from Modbus Slave devices

When the GW-7553-B / GW-7553-M acts as a Modbus Slave device, it can
receive query message from Modbus Master device and then saving to internal
DO、AO memory space. It can also send response message to Modbus Master

device through internal DI、AI data, as shown in Figure 20、Figure 21.

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Figure 20 The GW-7553-B / GW-7553-M receive data from Modbus Master device

Figure 21 The GW-7553-B / GW-7553-M output data to Modbus Master device

3.3 Communication protocol transfer

In section 3.1 and 3.2, we can understand that data exchange is through DI、
DO、 AI、 AO memory space of the GW-7553-B / GW-7553-M between

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PROFIBUS Master、Modbus and the GW-7553-B / GW-7553-M. When the GW­7553-B / GW-7553-M acts as a Modbus Master device, the data exchange runs

continuously between PROFIBUS Master、Modbus and the GW-7553-B / GW­7553-M, as shown in Figure 22、Figure 23.

Figure 22 GW-7553-B / GW-7553-M (master mode) communication protocol
transfers

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Figure 23 GW-7553-B / GW-7553-M (master mode) flowchart

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When the GW-7553-B / GW-7553-M acts as a Modbus Slave device, the data
exchange runs continuously between PROFIBUS Master and the GW-7553-B /
GW-7553-M and the data exchange runs between Modbus Master device and the
GW-7553-B / GW-7553-M, when GW-7553-B / GW-7553-M receive query
message from Modbus Master device, as shown in Figure 24、Figure 25.

Figure 24 GW-7553-B / GW-7553-M (slave mode) communication protocol
transfer

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Figure 25 GW-7553-B / GW-7553-M (slave mode) flowchart

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3.4 PROFIBUS DP-V1 Acyclic Service

DP-V1 is the extension of DP-V0, it extend the original cyclic data exchange to
acyclic one. Traditional data-exchange exploits default SAP for cyclic data­exchange. In DP-V1, Additional SAPs(49, 50, 51) for acyclic service, The SAP 49
is Resource Manager for manage each class 2 connection; The SAPs 50 and 51
are Read/Write/Alarm_Ack access point for class 1 connection.

DPV1 extension consists of 2 main parts : 1. MSAC_C1 2. MSAC_C2. For details,
as shown in Table 11.

Table 11 Service for DPV1 acyclic comminication

service

MSAC_C1

Class 1 master reads a data block from the slave (Read)

Class 1 master writes a data block to the slave (Write)

An alarm is transmitted from the slave to the master, which
explicitly acknowledge receipt (Alarm、Alarm_Ack)

MSAC_C2

Setup of a connection for acyclic communication between the
calss 2 master and the slave (Initiate)

Class 2 master reads a data block from the slave (Read)

Class 2 master writes a data block to the slave (Write)

Class 2 master can write application-specific data acyclically to
the slave and, if required, read data from the slave in the same
cycle (Data Transport)

Termination of a connection for acyclic communication between
the calss 2 master and the slave (Abort)

DP-V1 slave provide a unique acyclic service entry SAP 49, this SAP called
Resource Manager. Resource Manager play the role of coordinator, it coordinate
multiple remote connection at one time. Before acyclic data-exchange, class 2
master send an initiate request to SAP 49, then resource manager search for an
available SAP(48~0) to response these information to Class 2 Master. After Class
2 Master receives initiate response, it applies the new SAP to request information
you want. In contrast to C1 Master, C2-Master supports Data-Transport service
for read & write at one cycle. If DP-V1 services were no more need, Class 2
Master sent the Abort request to terminate the connection. During the connection,
DP-Slave start watchdog timer to monitor the C2 DP-V1 telegram (C2-Init, C2­Abort, C2-Write, C2-Read, C2-DataTransport, C2-IDLE). If watchdog timer
didn‟t clear by C2-IDLE, DP-slave will terminate this connection automatically.

The Information in DP-V1 is addressing by Slot and Index. The slot(0~255)
addresses the module and the index(0~255) addresses the data blocks assigned to

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a module. Each data block can be up to 244 bytes. Length is used to indicate the
read/write length. If the information addressing use non-exist slot、index or

length, the corresponding error code will be signaled(see Table 12、Figure 26

Error code/Error class), the reply is sent to the master.

Table 12 Error code/Error class

Error_Class

Meaning

Error_Code

10

application

0 = read error
1 = write error
2 = module failure
3 to 7 = reserved
8 = version conflict
9 = feature not supported
10 to 15 = user specific

11

access

0 = invalid index
1 = write length error
2 = invalid slot
3 = type conflict
4 = invalid area
5 = state conflict
6 = access denied
7 = invalid range
8 = invalid parameter
9 = invalid type
10 to 15 = user specific

12

resource

0 = read constrain conflict
1 = write constrain conflict
2 = resource busy
3 = resource unavailable
4 to 7 = reserved
8 to 15 = user specific

Figure 26 Error code/Error class

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DP-V1 services supported by GW-7553-B / GW-7553-M are Read、Write and
Data Transport service, Alarm_Ack didn‟t supported. List shown below is the

Slot-Index mapping table.

Table 13 Slot-Index mapping table

Slot

Modbus Type

Index

Length

1

N/A

0

1

2~32

RDI

NO. of relay/Coil

1

RDO

WDO

RAI

NO. of Words

2

RAO

WAO

33~255

N/A

N/A

N/A

Slot 1 is used for the system setting module. Because the user must add “System
setting module” at the first module before the other modules, else the GW-7553-B
/ GW-7553-M will send the diagnostic messages to PROFIBUS Master and the
system will be abnormal.

Slot 2~32 is used for Modbus modules. Index mapped input/output channel from
corresponding module. If a digital module(DI/DO module), one index is only one
bit. If an analog module(AI/AO module), one index is one word.

Slot 33~255 is not supported by GW-7553-B / GW-7553-M. Because the
maximum number of I/O modules is 32.

Note：
The data block fixed by DPV1 write acyclic service will be overwritten by DPV0
cyclic service. We provide an option in “slot 1、index 0、length 1” to change the
priority of DPV1 write acyclic service . The Default value is 0. To achieve the

higher priority of DPV1 write acyclic service , the value has to be set to “1”.

Example 1:
If user setup 3 modules in GW-7553-B / GW-7553-M, system setting module、2