USR IOT USR-G781 User manual

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USR-G781 User Manual
File Version: V1.0.06.02

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Contents
USR-G781 User Manual..........................................................................................................................................1
Brief Introduction............................................................................................................................................. 4
Features............................................................................................................................................................... 4
1. Get Start................................................................................................................................................................... 5
1.1. Application.................................................................................................................................................. 5
1.1.1. Application Diagram...................................................................................................................... 5
1.1.2. Hardware Dimensions................................................................................................................... 6
1.1.3. Hardware Interface........................................................................................................................ 7
1.1.4. LED Indicator...................................................................................................................................8
1.2. Module Default Parameters.....................................................................................................................8
1.3. Basic Parameters....................................................................................................................................... 9
1.4. Frequency Band........................................................................................................................................10
1.5. Hardware Introductions.........................................................................................................................10
2. Product Functions............................................................................................................................................... 12
2.1. APN..............................................................................................................................................................12
2.2. Router Functions......................................................................................................................................13
2.2.1. Configuration procedure............................................................................................................ 13
2.2.2. Networking mode......................................................................................................................... 14
2.2.2.1. WAN+LAN+4G.....................................................................................................................14
2.2.2.2. LAN+LAN+4G......................................................................................................................14
2.2.3. Features.......................................................................................................................................... 15
2.2.3.1. 4G Interface........................................................................................................................ 15
2.2.3.2. LAN Interface......................................................................................................................15
2.2.3.3. WAN Interface.................................................................................................................... 16
2.2.3.4. DHCP Server function.......................................................................................................16
2.2.3.5. VPN function.......................................................................................................................17
2.2.3.6. Static Routes function...................................................................................................... 17
2.2.3.7. Static IP binding................................................................................................................ 18
2.2.3.8. Network diagnosis............................................................................................................ 18
2.2.3.9. Firewall................................................................................................................................19
2.3. DTU Functions.......................................................................................................................................... 21
2.3.1. Work Mode..................................................................................................................................... 21
2.3.1.1. Transparent Mode.............................................................................................................21
2.3.1.2. HTTPD Client Mode.......................................................................................................... 23
2.3.2. Serial Port.......................................................................................................................................24
2.3.2.1. Parameters range..............................................................................................................24
2.3.2.2. Serial Package Methods................................................................................................... 24
2.3.2.3. Baud Rate Synchronization.............................................................................................24
2.3.3. Features.......................................................................................................................................... 25
2.3.3.1. Identity packet Function................................................................................................. 25
2.3.3.2. Heartbeat packet Function..............................................................................................26
2.4. Basic functions..........................................................................................................................................26

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2.4.1. Reload by Hardware.....................................................................................................................26
3. Parameter Setting............................................................................................................................................... 27
3.1. Web Server Configuration...................................................................................................................... 27
3.2. AT Command............................................................................................................................................. 28
3.2.1. Serial AT Command...................................................................................................................... 28
3.2.2. Setup software...............................................................................................................................28
3.2.3. Transparent AT Command..........................................................................................................28
4. Contact Us..............................................................................................................................................................29
5. Disclaimer............................................................................................................................................................. 29
6. Update History..................................................................................................................................................... 29

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Brief Introduction
USR-G781 is a 3G&4G DTU which apply to LTE WCDMA and GPRS. Serial RS232 or RS485 can be transfer to
Internet server via LTE technology. G781 has two Ethernet port for networking accessory.
Features
ARM 9 core and Linux system based.
Supports 2G 3G and 4G LTE. Different version for America, Europe, Australia and other areas.
Support 2 Ethernet RJ45 port. One LAN port, and another one can be set as WAN port or LAN port.
Support 1 SIM card socket.
Support PPTP VPN. LT2P, IPSEC and Open VPN are on developing.
Support DDNS, static routing and firewall.
Support NTP and clock synchronization.
Support Web Server configuration.
Supports 4 connections online simultaneously, supports TCP and UDP
Supports sending network identity packet.
Supports sending heartbeat packet data to network or serial port
Supports 2 serial work modes: Network transparent transmission mode and HTTPD mode
Dual watchdog timer for stability.

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1. Get Start
Product link:
http://www.usriot.com/p/g781/
Setup software:
http://www.usriot.com/usr-g781-setup-software-v1-0-0-0/
Figure 1 Download Page
If you have any question, please submit it back to customer center: http://h.usriot.com
1.1. Application
1.1.1.Application Diagram
When you start using module, the first step is to configure APN settings.
2.1.APN is chapter for APN settings.

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Figure 2 Application diagram
1.1.2.Hardware Dimensions
units: mm
Figure 3 Hardware dimensions

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1.1.3.Hardware Interface
Figure 4 Hardware interface
Figure 5 Hardware interface

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Interface
Information
LTE antenna
Stick antenna and sucker antenna for chosen
Reload button
Press button for 3~15s to reload to factory settings
Ethernet port
WAN/LAN port can be switch by serial command
Power supply
DC 9~36V power supply
RS232 DB9
female
5 wires RS232(TXD/RXD/GND/RTS/CTS)
RS485 terminal
3 wires RS485: A+/B-/GND
SIM card socket
Insert SIM card here
Figure 6 Interface information
1.1.4.LED Indicator
Indicator
Status
Power
On: Power on
Off: Power off
NET
Red: 2G network
Blue: 3G network
Purple: 4G network
Off: No network
WORK
On: Working
Off: Not working
SIM
On: SIM card detected
Off: SIM card not detected
LINKA
On: Socket A connected
Off: Socket A disconnected
LINKB
On: Socket B connected
Off: Socket B disconnected
TXD
On: Sending data to serial
Off: No data sending to serial
RXD
On: Receiving data from serial
Off: No data receiving from serial
Figure 7 Hardware Indicator
1.2. Module Default Parameters
Work mode
Transparent mode
Server Address
test.usr.cn
Server Port
2317
Serial Parameters
115200,8,1,None
Heartbeat packet
www.usr.cn
Figure 8 Default parameters

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1.3. Basic Parameters
Parameter
Index
SIM card and antenna
SIM/USIM card
Six pin SIM card interface, 3V/1.8V SIM card
Antenna
SMA interface, 5dBi antenna
Hardware Parameters
Wired Internet interface
WAN*1 and LAN*1
Data Interface
RS232:300bps - 460800bps
RS485:300bps - 460800bps
Indicator LED
LINKA, LINKB, TXD, RXD, POWER, NET, WORK, SIM
Working Voltage
DC 9V~36V
Working Current
Average current 180mA@12V
Peak Current 300mA@12V
Working Temp.
-25℃- 85℃
Storage Temp.
-40℃- 125℃
Working humidity
10%~90%
Storage humidity
5%~90%
Software Parameters
Work Mode
Transparent Mode, HTTPD Client Mode
Setting Command
AT+ Command Structure
Network protocol
TCP/UDPDNS/HTTP/FTP
Max TCP connections
4
User Configuration Method
Setting Software,AT command and Web Server
configuration
Software Functions
VPN
Support PPTP
Static routing management
Support
Firewall
Support
Network diagnosis
Support
Remote Management
Support
Transparent Transmission
Support TCP Server/TCP Client/UDP Server/UDP Client
HTTP Protocol
Transmission
Support
Heartbeat Packet
Support
Identity Packet
Support IMEI/ICCID/self-defined identity packet
Baud Rate Synchronization
Support
USR Cloud
Support
Figure 9 Basic parameters

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1.4. Frequency Band
G781
G781-43
G781-E
G781-V
G781-A
G781-AU
Operatin
g Band
Operatin
g Band
Operatin
g Band
Operatin
g Band
Operatin
g Band
Operatin
g Band
FDD-LTE
1
1
1
1
2
2
3
3
3
3
4
4
4
5
5
7
7
8
8
8
12
13
20
28
TDD-LTE
38
38
38
39
39
40
40
40
40
41
41
41
WCDMA
1
1
1
1
2
2
4
5
5
5
8
8
8
8
CDMA1X
800MHz
CDMA2000-EVDO
GPRS
2
3
3
3
3
8
8
8
5
8
Figure 10 Frequency Band
1.5. Hardware Introductions
Below is the hardware interface schematic diagram of USR-G781

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Figure 11 Hardware interface schematic diagram

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2. Product Functions
2.1. APN
Different operator have different APN(access point name), if you use the SIM card from the operator. You must
know the APN. You can ask your SIM card operator for APN.
There are four parameters about APN. Those are APN Name, User Name, Password and Encrypt. Sometimes only
configure APN Name is enough. User can configure the APN settings by Web Server or Setup software as follows:
Figure 12 APN configuration

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2.2. Router Functions
This chapter introduces the Router functions of USR-G781, as the following diagram shown, you can get an
overall knowledge of it.
Figure 13 Router Functions diagram
2.2.1. Configuration procedure
Basic procedure as follows:
Step1: Keep G781 in power off condition.
Step2: Insert SIM card.
Step3: Connect antenna.
Step4: Power the G781.
Step5: Wait about one minute, NET LED light with purple, G781 can connect to 4G network.
Connection diagram as follow:
Figure 14 Application diagram
User can access network through G781. PC connect to G781 by LAN interface and PC should open DHCP function.

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2.2.2. Networking mode
2.2.2.1. WAN+LAN+4G
Diagram as follows:
Figure 15 WAN+LAN+4G Application diagram
In this mode, users can connect to Internet through WAN or 4G. Default configuration is WAN has higher priority.
When router can’t connect Internet through WAN, it will change to 4G network.
2.2.2.2. LAN+LAN+4G
Diagram as follows:
Figure 16 LAN+LAN+4G Application diagram
In this mode, two devices can connect to router through LAN and access the Internet by 4G network. To adopt

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LAN+LAN+4G mode, user just need set WAN/LAN interface to LAN interface by Web Server as follow:
Figure 17 WAN/LAN interface switch
2.2.3. Features
2.2.3.1. 4G Interface
G781 support one 4G interface to connect Internet. Functional diagram as follows:
Figure 18 4G Interface
When user use 4G interface, the most important thing is to configure the APN parameters. User can refer to 2.1.
APN to configure the APN parameters.
2.2.3.2. LAN Interface
When user set WAN/LAN interface into LAN mode, G781 will have two LAN interface.
Default settings: Static IP address: 192.168.1.1; Subnet mask: 255.255.255.0; Open DHCP Server function.

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User can configure LAN interface by Web Server as follow:
Figure 19 LAN interface configuration
2.2.3.3. WAN Interface
G781 has one WAN interface. Support DHCP Client and Static Address, default setting is DHCP Client.
User can configure WAN interface by Web Server as follow:
Figure 20 WAN interface configuration
2.2.3.4. DHCP Server function
DHCP default range of distribution from 192.168.1.100 to 192.168.1.254 and default address expire time is
86400 seconds (ten days). Address range and expire time can be changed.
User can configure DHCP Server function parameters by Web Server as follow:

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Figure 21 DHCP Server function configuration
2.2.3.5. VPN function
G781 only support PPTP mode to achieve VPN function now. And Subsequent versions will support L2TP, GRE,
openvpn, ipsec mode.
User can configure VPN function by Web Server as follow:
Figure 22 VPN function configuration
2.2.3.6. Static Routes function
User can set G781 Static Route table to achieve self-defined routing rules.
User can configure Static Routes by Web Server as follow:

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Figure 23 Static Routes function configuration
2.2.3.7. Static IP binding
User can bind IP address with MAC address and G781 will distribute fixed IP address to some devices.
User can bind IP and MAC by Web Server as follow:
Figure 24 Static IP binding function configuration
2.2.3.8. Network diagnosis
User can use ping a specified address to check the connection status.
User can use Network diagnosis function by Web Server as follow:

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Figure 25 Network diagnosis
2.2.3.9. Firewall
By use Firewall function, user can set firewall Filter Table rules and Forward Table rules to manage Network
security. And user can also add, delete and modify Firewall rules by sending iptables commands.
User can configure Firewall configuration by Web Server as follow:
Filter Table rules:
Figure 26 Filter Table rules configuration
Forward Table rules:

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Figure 27 Forward Table rules configuration
Sending iptables commands:
Figure 28 Sending iptables commands