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Serial Transmit

Send serial data to UART port

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Add-On Required: This feature requires the Simulink Coder Support Package for NXP FRDM-K64F Board add-on.

  • Serial Transmit block

Libraries:
Simulink Coder Support Package for NXP FRDM-K64F Board

Description

The Serial Transmit block sends serial data to the Universal Asynchronous Receiver Transmitter (UART) port that is on the board.

To select the UART port, use the UART parameter.

To send the values to the UART port, use the Tx pin on the port. To specify the Tx (transmitting) pin, go to Configuration Parameters > Hardware Implementation pane > UARTx > Tx Pin.

The block inherits the data type from the signal at the input port.

During the external mode simulation, the block outputs the results from the executable running on the target hardware.

During simulation in all other modes, the block outputs zeroes.

Ports

Input

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The port accepts values as an [Nx1] or [1xN] array from your model.

The port sends the values to the UART port using the Tx pin on the port. To specify the Tx pin for the UART Serial Interface, go to Configuration Parameters > Hardware Implementation pane > UARTx > Tx Pin.

Data Types: int8 | uint8 | int16 | uint16 | int32 | uint32 | single | double | Boolean

Output

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When you select the Output status parameter, the Status port becomes available.

The port outputs 0 for a successful send operation. A value of 0 indicates that the input data is sent to the UART port at the given time step.

The port outputs 32 for an unsuccessful send operation. A value of 32 indicates that the input data received in the previous time step is not sent.

Dependencies

You can choose to display the status of the send operation only in the non-blocking mode. To run the send operation in the non-blocking mode, clear the Wait until data received parameter. To make the Status port available, select the Output status parameter, and then click Apply.

Data Types: uint8

Parameters

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Select the UART port on the board to which the block sends data. The Tx port on the block sends the values to the UART port using the Tx pin on the port. To specify the Tx pin for the UART Serial Interface, go to Configuration Parameters > Hardware Implementation pane > UARTx > Tx Pin.

  • on — When you select this parameter, the send operation runs in the Blocking mode. If data received in the previous time step is sent, the block accepts data from the input port. If the send operation is in progress, the block waits for the data to be sent, and then it accepts data from the input port.

    A task overrun occurs if the input data received in the previous time is not sent when the next send operation is scheduled to begin. To fix overruns:

    • Increase sample time of the block.

    • Reduce the length of data at the input port.

  • off — When you clear this parameter, the send operation runs in the Non-blocking mode. When sending data, if the transmission of the data received in the previous time step is still in progress, the data at the input port at the given time step is dropped.

Dependencies

When you select this parameter, the Status port is hidden.

When you select this parameter, the Status port becomes available.

The port outputs 0 for a successful send operation. A value of 0 indicates that the input data is sent to the UART port at the given time step.

The port outputs 32 for an unsuccessful send operation. A value of 32 indicates that the input data received in the previous time step is not sent.

Dependencies

You can choose to display the status of the send operation only in the non-blocking mode. To run the send operation in the non-blocking mode, clear the Wait until data received parameter. To make the Status port available, select the Output status parameter, and then click Apply.

See Also