USART DMAC Example

Purpose

This example demonstrates how to use DMAC to implement USART peripherals function in serial mode.

Requirements

This package can be used with all SAM-EK with UART/USART and DMAC.

Description

On start up, the debug information is dumped to on-board UART port. A terminal application, such as HyperTerminal, is used to monitor these debug information. Open another HyperTerminal to connect with on-board USART port. Then the program works in ECHO mode, so USART will send back anything it receives from the HyperTerminal. You can send a text file from the HyperTerminal connected with USART port to the device (without any protocol such as X-modem).

Note

The text file size must be equal to BUFFER_SIZE(32 bytes in this example).

Usage

1. Build the program and download it into the evaluation boards.
2. Connect a serial cable to the UART port for the evaluation kit.
3. On the computer, open and configure a terminal application (e.g., HyperTerminal on Microsoft Windows) with these settings:
   • 115200 bauds
   • 8 bits of data
   • No parity
   • 1 stop bit
   • No flow control
4. In the terminal window, the following text should appear:

   -- USART DMAC Example --
   -- xxxxxx-xx
   -- Compiled: xxx xx xxxx xx:xx:xx --

5. Send a file in text format from the HyperTerminal connected with USART port to the device. On HyperTerminal, this is done by selecting "Transfer -> Send Text File"(this does not prevent you from sending binary files). The transfer will start and then you could read the file in the HyperTerminal.