FPGA开发——Hello_world例程

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/*
 * helloworld.c: simple test application
 *
 * This application configures UART 16550 to baud rate 9600.
 * PS7 UART (Zynq) is not initialized by this application, since
 * bootrom/bsp configures it to baud rate 115200
 *
 * ------------------------------------------------
 * | UART TYPE   BAUD RATE                        |
 * ------------------------------------------------
 *   uartns550   9600
 *   uartlite    Configurable only in HW design
 *   ps7_uart    115200 (configured by bootrom/bsp)
 */

#include <stdio.h>
#include "platform.h"
#include "xil_printf.h"
#include <sleep.h>

/*
*init_platform函数的作用是使能caches和初始化uart
*cleanup_platform函数的作用是取消使能caches
*实际上这两个函数在该工程中并没有启动任何作用，因为这两个函数是针对于特定平台如Microblaze的，对于我们使用的ZYNQ平台而言是不起作用的
*出于平台的通用性和可移植性，此处我们保留这两个函数。
*另外需要注意程序中打印字符串“Hello World”使用的是print()函数，而不是C语言里的printf()函数
print()函数是Xilinx定义的一个用于打印字符串的函数，调用该函数需要包含头文件“xil_printf.h”。
*/

int main()
{
    init_platform();
	while(1){
		print("hello world\r\n");
		sleep(1);
		cleanup_platform();
	}
    return 0;
}