MCUXpresso SDK Documentation

usart_hardware_flow_control

usart_hardware_flow_control#

Overview#

The usart_hardware_flow_control example project demonstrates the usage of the hardware flow control function. This example sends data to itself(loopback), and hardware flow control is enabled in the example. The CTS(clear-to-send) pin is for transmiter to check if receiver is ready, if the CTS pin is asserted, transmiter starts to send data. The RTS(request-to-send) pin is for receiver to inform the transmiter if receiver is ready to receive data. So, please connect RTS to CTS pin directly.

Supported Boards#

FRDM-MCXW23
Hardware requirements
  • Type-C USB cable

  • FRDM-MCXW23 Board

  • Personal Computer

Board settings

USART hardware flow control on one board. The USART sends data to itself(loopback), and hardware flow control function is enabled on this example. So please make sure the correct connection for example.

Pin Name    Board Location    connect to     Pin Name    Board Location
USART_TX    J5-5              ----------     USART_RX    J5-6
USART_CTS   J2-9              ----------     USART_RTS   J1-5
Prepare the Demo
  1. Connect a USB cable between the host PC and the FRDM board J10.

  2. Open a serial terminal with the following settings:

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  3. Download the program to the target board.

  4. Either press the reset button on your board or launch the debugger in your IDE to begin running the demo.

Running the demo

When the demo runs successfully, the log would be seen on the terminal like:

This is USART hardware flow control example on one board.
This example will send data to itself and will use hardware flow control to avoid the overflow.
Please make sure you make the correct line connection. Basically, the connection is: 
      USART_TX    --     USART_RX    
      USART_RTS   --     USART_CTS   
Data matched! Transfer successfully.

LPCXpresso54628
Hardware requirements
  • Micro USB cable

  • LPCXpresso54628 board

  • Personal Computer

Board settings

USART hardware flow control on one board. The USART sends data to itself(loopback), and hardware flow control function is enabled on this example. So please make sure the correct connection for example.

Pin Name    Board Location    connect to     Pin Name    Board Location
USART_TX    J13   Pin 13      ----------     USART_RX    J13   pin 15
USART_CTS   J13   Pin 16      ----------     USART_RTS   J13   Pin 14
Prepare the Demo
  1. Connect a micro USB cable between the host PC and the LPC-Link USB port (J8) on the target board.

  2. Open a serial terminal with the following settings:

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  3. Download the program to the target board.

  4. Either press the reset button on your board or launch the debugger in your IDE to begin running the demo.

Running the demo

When the demo runs successfully, the log would be seen on the terminal like:

This is USART hardware flow control example on one board.
This example will send data to itself and will use hardware flow control to avoid the overflow.
Please make sure you make the correct line connection. Basically, the connection is:
      USART_TX    --     USART_RX
      USART_RTS   --     USART_CTS
Data matched! Transfer successfully.
RD-RW612-BGA
Hardware requirements
  • Micro USB cable

  • RD-RW612-BGA board

  • Personal Computer

Board settings

USART hardware flow control on one board. The USART sends data to itself(loopback), and hardware flow control function is enabled on this example. So please make sure the correct connection for example.

Pin Name    Board Location    connect to     Pin Name    Board Location
USART_TX    HD2   Pin 4       ----------     USART_RX    HD2   pin 3
USART_CTS   HD11  Pin 14      ----------     USART_RTS   HD11  Pin 8
Prepare the Demo
  1. Connect a micro USB cable between the PC host and the MCU-Link USB port (J7) on the board

  2. Open a serial terminal with the following settings:

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  3. Download the program to the target board.

  4. Launch the debugger in your IDE to begin running the demo.

Running the demo

When the demo runs successfully, the log would be seen on the terminal like:

This is USART hardware flow control example on one board.
This example will send data to itself and will use hardware flow control to avoid the overflow.
Please make sure you make the correct line connection. Basically, the connection is:
      USART_TX    --     USART_RX
      USART_RTS   --     USART_CTS
Data matched! Transfer successfully.

MCXW23-EVK
Hardware requirements
  • Mini/micro USB cable

  • MCXW23-EVK Board

  • Personal Computer

Board settings

USART hardware flow control on one board. The USART sends data to itself(loopback), and hardware flow control function is enabled on this example. So please make sure the correct connection for example.

Pin Name    Board Location    connect to     Pin Name    Board Location
USART_TX    J17-4             ----------     USART_RX    J17-3
USART_CTS   J24-3             ----------     USART_RTS   J18-3
Prepare the Demo
  1. Connect a USB cable between the host PC and the EVK board J33.

  2. Open a serial terminal with the following settings:

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  3. Download the program to the target board.

  4. Either press the reset button on your board or launch the debugger in your IDE to begin running the demo.

Running the demo

When the demo runs successfully, the log would be seen on the terminal like:

This is USART hardware flow control example on one board.
This example will send data to itself and will use hardware flow control to avoid the overflow.
Please make sure you make the correct line connection. Basically, the connection is: 
      USART_TX    --     USART_RX    
      USART_RTS   --     USART_CTS   
Data matched! Transfer successfully.

MIMXRT685-EVK
Hardware requirements
  • Micro USB cable

  • EVK-MIMXRT685 board

  • Personal Computer

Board settings

USART hardware flow control on one board. The USART sends data to itself(loopback), and hardware flow control function is enabled on this example. So please make sure the correct connection for example.

Pin Name    Board Location    connect to     Pin Name    Board Location
USART_TX    J28   pin 5       ----------     USART_RX    J28   pin 4
USART_CTS   J28   pin 3       ----------     USART_RTS   J28   pin 2

Remove jumper JP30.

Prepare the Demo
  1. Connect a micro USB cable between the PC host and the CMSIS DAP USB port (J5) on the board

  2. Open a serial terminal with the following settings:

    • 115200 baud rate

    • 8 data bits

    • No parity

    • One stop bit

    • No flow control

  3. Download the program to the target board.

  4. Launch the debugger in your IDE to begin running the demo.

Running the demo

When the demo runs successfully, the log would be seen on the terminal like:

This is USART hardware flow control example on one board.
This example will send data to itself and will use hardware flow control to avoid the overflow.
Please make sure you make the correct line connection. Basically, the connection is:
      USART_TX    --     USART_RX
      USART_RTS   --     USART_CTS
Data matched! Transfer successfully.