usart-iar.rar_ATMEL USART_IAR的USART查看_at91sam7x512_couragehyf

/* ---------------------------------------------------------------------------- * ATMEL Microcontroller Software Support * ---------------------------------------------------------------------------- * Copyright (c) 2008, Atmel Corporation * * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * - Redistributions of source code must retain the above copyright notice, * this list of conditions and the disclaimer below. * * Atmel's name may not be used to endorse or promote products derived from * this software without specific prior written permission. * * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * ---------------------------------------------------------------------------- */ //------------------------------------------------------------------------------ /// \dir "Basic USART Hardware Handshaking Project" /// /// !!!Purpose /// /// This example demonstrates the hardware handshaking mode (i.e. RTS/CTS) /// provided by the USART peripherals on AT91 microcontrollers. The practical /// use of hardware handshaking is that it allows to stop transfer on the USART /// without losing any data in the process. This is very useful for applications /// that need to program slow memories for example. /// /// !!!Requirements /// /// This example can be used on any AT91 evaluation kit, except when they do /// not provide an USART serial port (i.e. on AT91SAM9261-EK, AT91SAM7L-EK and /// AT91SAM7L-STK). /// /// !!!Description /// /// The provided program uses hardware handshaking mode to regulate the data /// rate of an incoming file transfer. A terminal application, such as /// hyperterminal, is used to send a text file to the device (without any /// protocol such as X-modem). The device will enforce the configured /// bytes per second (bps) rate with its Request To Send (RTS) line. /// /// Whenever the data rate meet or exceed the configurable threshold, the device /// stops receiving data on the USART. Since no buffer is provided to the PDC, /// this will set the RTS line, telling the computer to stop sending data. Each /// second, the current data rate and total number of bytes received are /// displayed; the transfer is also restarted. /// /// Note that the device may receive slightly less bytes than the actual file /// size, depending on the nature of the file. This does NOT mean that bytes /// have been lost: this is simply an issue with how line breaks are transmitted /// by the terminal. It is therefore better to use binary files, as they most /// often do not contain line breaks. For example, send one of the object files /// generated by the compiler. /// /// !!!Usage /// /// -# Build the program and download it inside the evaluation board. Please /// refer to the <a href="http://www.atmel.com/dyn/resources/prod_documents/doc6224.pdf">SAM-BA User Guide</a>, /// the <a href="http://www.atmel.com/dyn/resources/prod_documents/doc6310.pdf">GNU-Based Software Development</a> /// application note or to the <a href="ftp://ftp.iar.se/WWWfiles/arm/Guides/EWARM_UserGuide.ENU.pdf">IAR EWARM User Guide</a>, /// depending on your chosen solution. /// -# Connect a serial cable to the USART0 port on the evaluation kit. It will /// most often be labeled "RS232 COM port". /// -# On the computer, open and configure a terminal application (e.g. /// HyperTerminal on Microsoft Windows) with these settings: /// - 115200 bauds /// - 8 data bits /// - No parity /// - 1 stop bit /// - Hardware flow control (RTS/CTS) /// -# Start the application. The following traces shall appear on the terminal: /// \code /// -- Basic USART Hardware Handshaking Project xxx -- /// -- AT91xxxxxx-xx /// -- Compiled: xxx xx xxxx xx:xx:xx -- /// Bps: 0; Tot: 0 /// \endcode /// -# Send a file in text format 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 the device will update /// the bps and total counts on the terminal. /// -# Whenever the transfer is complete, the total number of bytes received /// should match the size of the sent file (unless it is a text file, see /// explanation in description section). //------------------------------------------------------------------------------ //------------------------------------------------------------------------------ // Headers //------------------------------------------------------------------------------ #include <board.h> #include <pio/pio.h> #include <usart/usart.h> #include <tc/tc.h> #include <aic/aic.h> #include <pmc/pmc.h> #include <utility/led.h> #include <utility/trace.h> #include <stdio.h> //------------------------------------------------------------------------------ // Local definition //------------------------------------------------------------------------------ #ifndef AT91C_ID_TC0 #if defined(AT91C_ID_TC012) #define AT91C_ID_TC0 AT91C_ID_TC012 #elif defined(AT91C_ID_TC) #define AT91C_ID_TC0 AT91C_ID_TC #else #error Pb define ID_TC #endif #endif /// Maximum Bytes Per Second (BPS) rate that will be forced using the CTS pin. #define MAX_BPS 500 /// Size of the receive buffer used by the PDC, in bytes. #define BUFFER_SIZE 1 //------------------------------------------------------------------------------ // Local variables //------------------------------------------------------------------------------ /// Pins to configure for the application. const Pin pins[] = { PINS_DBGU, //debug pin 定义 PIN_USART0_RXD, PIN_USART0_TXD, // PIN_USART0_CTS, // PIN_USART0_RTS PIN_USART1_RXD, PIN_USART1_TXD }; /// Number of bytes received between two timer ticks. volatile unsigned int bytesReceived = 0; /// Receive buffer. unsigned char pBuffer[BUFFER_SIZE]; /// String buffer. char pString[24]; //------------------------------------------------------------------------------ /// Configures LEDs \#1 and \#2 (cleared by default). //------------------------------------------------------------------------------ void ConfigureLeds(void) { LED_Configure(0); LED_Configure(1); LED_Configure(2); LED_Configure(3); } //------------------------------------------------------------------------------ // Local functions //------------------------------------------------------------------------------ //------------------------------------------------------------------------------ /// Interrupt handler for USART0. Increments the number of bytes received in the /// current second and starts another transfer if the desired bps has not been /// met yet. //------------------------------------------------------------------------------ void ISR_Usart0(void) { unsigned int status; // LED_Toggle(3); unsigned char ch ; // Read USART status // Receive buffer is full // if ((status & AT91C_US_RXBUFF) == AT91C_US_RXBUF