ATMEL AT91SAM7S64的RS485通讯程序源码

ATMEL的AT91SAM7S64的RS485通讯程序，中断方式接收，收到后立即通过485发送出去，485配置的管脚为PA5,PA6,PA7(收发使能)，开发环境是IAR Embedded Workbench 4.5。 对于一个数据串的接收也是类似的，采用收到数据中断方式，在收完完整的数据后（接收结束后）才能发送，否则会存在总线冲突。

//*----------------------------------------------------------------------------
//*         ATMEL Microcontroller Software Support  -  ROUSSET  -
//*----------------------------------------------------------------------------
//* The software is delivered “AS IS“ without warranty or condition of any
//* kind either express implied or statutory. This includes without
//* limitation any warranty or condition with respect to merchantability or
//* fitness for any particular purpose or against the infringements of
//* intellectual property rights of others.
//*----------------------------------------------------------------------------
//* File Name           : Cstartup_SAM7.c
//* object              : Low level initializations written in C for Tools
//* Creation            : 12/Jun/04
//* 1.2   28/Feb/05 JPP : LIB change AT91C_WDTC_WDDIS & PLL
//* 1.3   21/Mar/05 JPP : Change PLL Wait time
//* 1.4   21/Aug/05 JPP : Change MC_FMR Setting
//* 1.5   29/Aug/05 JPP : Change PLL error
//* 1.6   13/oct/05 JPP : Change comment
//*----------------------------------------------------------------------------

// Include the board file description
#include “Board.h“

// The following functions must be write in ARM mode this function called directly
// by exception vector
extern void AT91F_Spurious_handler（void）;
extern void AT91F_Default_IRQ_handler（void）;
extern void AT91F_Default_FIQ_handler（void）;

//*----------------------------------------------------------------------------
//* \fn    AT91F_LowLevelInit
//* \brief This function performs very low level HW initialization
//*        this function can be use a Stack depending the compilation
//*        optimization mode
//*----------------------------------------------------------------------------
void AT91F_LowLevelInit（ void）
{
 int            i;
 AT91PS_PMC     pPMC = AT91C_base_PMC;
    //* Set Flash Waite sate
	//  Single Cycle Access at Up to 30 MHz or 40
	    AT91C_base_MC->MC_FMR = AT91C_MC_FWS_1FWS ;

    //* Watchdog Disable
        AT91C_base_WDTC->WDTC_WDMR= AT91C_WDTC_WDDIS;

	//* Set MCK at 48 054 850
    // 1 Enabling the Main Oscillator:
        // SCK = 1/32768 = 30.51 uSecond
    	// Start up time = 8 * 6 / SCK = 56 * 30.51 = 146484375 ms
       pPMC->PMC_MOR = （（ AT91C_CKGR_OSCOUNT & （0x06 <<8） | AT91C_CKGR_MOSCEN ））;
        // Wait the startup time
        while（!（pPMC->PMC_SR & AT91C_PMC_MOSCS））;
	// 2 Checking the Main Oscillator Frequency （Optional）
	// 3 Setting PLL and divider:
		// - div by 14 Fin = 1.3165 =（18432 / 14）
		// - Mul 72+1: Fout =	96.1097 =（36864 *73）
		// for 96 MHz the erroe is 0.11%
		// Field out NOT USED = 0
		// PLLCOUNT pll startup time estimate at : 0.844 ms
		// PLLCOUNT 28 = 0.000844 /（1/32768）
       pPMC->PMC_PLLR = （（AT91C_CKGR_DIV & 14 ） |
                         （AT91C_CKGR_PLLCOUNT & （28<<8）） |
                         （AT91C_CKGR_MUL & （72<<16）））;


        // Wait the startup ti

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----

     文件     801280  2006-03-10 14:38  AT91SAM7S64-USART485\basicUSART-USB.doc

     文件         61  2008-06-18 17:05  AT91SAM7S64-USART485\note.txt

     文件        438  2005-03-02 13:52  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\main.html

     文件        269  2005-08-31 17:31  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\sam7.html

     文件      17137  2005-08-31 17:31  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\tools.html

     文件      10710  2008-06-18 17:05  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\USB.dep

     文件      24667  2006-03-06 10:42  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\USB.ewd

     文件      45429  2008-06-10 15:21  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\USB.ewp

     文件        157  2005-08-31 17:31  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\UsbSAM7.eww

     文件        244  2005-11-10 09:06  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\CVS\Entries

     文件         38  2005-11-10 09:04  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\CVS\Repository

     文件         58  2005-11-10 09:04  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\CVS\Root

     文件      74697  2008-06-18 17:01  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\Exe\USB.d79

     文件        967  2008-06-18 17:01  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\Exe\USB.sim

     文件      21049  2008-06-18 17:01  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\List\USB.map

     文件      21721  2006-03-07 17:58  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\Obj\cdc_enumerate.r79

     文件      40925  2006-03-06 10:40  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\Obj\Cstartup.r79

     文件      12819  2006-03-07 17:58  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\Obj\Cstartup_SAM7.r79

     文件      25307  2008-06-18 17:01  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\Obj\interrupt_Usart.r79

     文件      15517  2008-06-18 11:01  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\Obj\main.r79

     文件        932  2008-06-10 11:47  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\Obj\signal_process.pbi

     文件        751  2008-06-18 17:01  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\FLASH\Obj\USB.pbd

     文件      81530  2006-03-08 12:10  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\RAM_Debug\Exe\USB.d79

     文件      26937  2006-03-08 12:10  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\RAM_Debug\List\USB.map

     文件      21721  2006-03-08 10:43  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\RAM_Debug\Obj\cdc_enumerate.r79

     文件      40925  2006-03-06 10:39  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\RAM_Debug\Obj\Cstartup.r79

     文件      12819  2006-03-08 10:43  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\RAM_Debug\Obj\Cstartup_SAM7.r79

     文件      24399  2006-03-08 10:44  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\RAM_Debug\Obj\interrupt_Usart.r79

     文件      17122  2006-03-08 12:10  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\RAM_Debug\Obj\main.r79

     文件        627  2007-07-02 11:11  AT91SAM7S64-USART485\AT91SAM7S-BasicUSART_USB\compil\RAM_Debug\Obj\USB.pbd

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