UDP Send

Send data over UDP network to a remote device

Since R2020b

• 

Libraries:
Simulink Real-Time / IP

Description

The UDP Send block sends data over a UDP network to a remote device. The block can send data by using the connection between the MATLAB^® development computer and Speedgoat^® target computers or by using a dedicated Ethernet card. If you use a dedicated Ethernet card, use the Speedgoat configuration utility to configure the dedicated Ethernet board. One of the settings provided by this utility is the Default Gateway setting. When using the UDP Send block to broadcast to 255.255.255.255, the IP interface for broadcast is based on this Default Gateway setting.

To broadcast to all devices on the local subnetwork, set To IP address to 255.255.255.255. Otherwise, set To IP address to a valid IP address.

For unicasting, broadcasting and multicasting, the parameters Local IP address and Local port are optional. The Local IP address applies when the block executes in a real-time application on a target computer or in a model simulation on a development computer. If your model is running in Simulink^® on the development computer, you can use this block to transmit data to a remote device. In this case, the Windows^® operating system determines the network connection.

Examples

Target to Host Transmission by Using UDP

Use UDP blocks to send data from a target computer to a development computer.

• Open Model

Apply UDP Receive Block with Messages from Multiple IP Senders

Use UDP Receive blocks to receive messages from multiple IP addresses.

• Open Script

Ports

Input

Data — Data to transmit

vector

Vector of uint8 containing data to transmit over the UDP network. To determine how many bytes of data to transmit, use the Length input port. If you enable the Enable Simulink messages parameter, the data type is UDP_Packet. Use the slrealtime.createUDPPacketBusObj function to create the Simulink.Bus type Ethernet_Packet. This data type consists of:

• IP_Address: DataType: uint8, Complexity: real, Dimensions: [4 1]

• IP_Port: DataType: uint16, Complexity: real, Dimensions: 1

• Length: DataType: uint16, Complexity: real, Dimensions: 1

• Data: DataType: uint8, Complexity: real, Dimensions: [75 1]

Data Types: uint8 | UDP_Packet

Length — Number of bytes of data to transmit

double

This port is available when you disable the Enable Simulink messages parameter. The Length determines the number of bytes of data to transmit. Specify the width of the Data vector as the maximum number of bytes that you expect to transmit.

Parameters

Use host-target connection — Use Ethernet connection between development and target computers

'off' (default) | 'on'

Dependency

When you select this parameter, it deactivates the Local IP address parameter and excludes the ports 1 through 1023 and 5500 through 5560 from use by UDP.

Programmatic Use

Block Parameter: useHostTargetConn

To IP address — IP address of target device

10.10.10.10 (default) | x.x.x.x

Specifies IP address of target device. To broadcast to all devices on the local subnetwork, send to 255.255.255.255.

Programmatic Use

Block Parameter: toAddress

To port — UDP port of target device

34 (default) | 1–65535

Specify the UDP port of target device. With To IP address, this parameter defines the destination of the data transmission.

Programmatic Use

Block Parameter: toPort

Sample time (-1 for inherited) — Sample time of block

-1 (default) | numeric

Enter the base sample time or a multiple of the base sample time.

Programmatic Use

Block Parameter: sampleTime

Enable Simulink messages — Data as messages

off (default) | on

The Enable Simulink messages directs the block to treat data as messages. When enabled, the Length port is removed.

Programmatic Use

Block Parameter: MessageIn

Advanced Parameters

Local IP address — Source IP address for sending data

no value (default) | x.x.x.x

When Local IP address is set to Use host-target connection, the block uses the connection between the development and target computers. When To IP address is specified as a multicast address, the local IP address is used to determine the outbound interface over which multicast datagrams are sent. The default value for the Local IP address field is no value. This empty field means that the operating system chooses the Local IP address for UDP transmission.

Programmatic Use

Block Parameter: ipAddress

Local port — Source UDP port to transmit data

no value (default) | 0–65535 | -1

Specifies local UDP port to transmit data.

Ports 1 through 1023 and 5500 through 5560 are reserved for Simulink Real-Time communications.

The value 0, −1, or no value mean that the block transmits data by using any available port.

Programmatic Use

Block Parameter: localPort

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2020b

R2021b: Changed Parameters Local IP Address and Local Port

The parameters for the UDP Send block have changed. For unicasting, broadcasting, and multicasting, the parameters Local IP address and Local port are optional.

R2021a: Added Multicast Support

The UDP Multicast Receive block was added, and the UDP Send block has multicast support. These blocks provide multicast message support for the UDP communications protocol.