NIOS学习笔记

刚刚开始使用NIOS II 在使用的时候出现了很多的问题，我现在把我经常遇到的问题整理一下，希望能给各位一些帮助。1、SDRAM不能正常读写我刚刚开始使用SDRAM的时候，经过了两天的时间调试，才把SDRAM 调试通，经常会遇到很多的问题，如果调试不通，首先应该检查一下硬件，看看有没有时钟信号。晶振起震吗，然后在看看PLL的设置，我当时就是因为PLL的问题，搞死我了。我的e0输出当时定的是-60，后来改了0才对的，但还是有时候对有时候不对，可能NIOS II这个软件有问题。2、UART的问题我遇到的UART的问题如下
**** Build of configuration Debug for project hello_led_0 ****make -s all includes Compiling hello_led.c...Linking hello_led_0.elf.../cygdrive/c/altera/72/nios2eds/bin/nios2-gnutools/H-i686-pc-cygwin/bin/../lib/gcc/nios2-elf/3.4.1/../../../../nios2-elf/lib/mno-hw-mul/pg//libc.a(closer.o)(.text+0x24): In function `_close_r':/build/nios2eds-gnutools-win32-7.2/bin/nios2-gnutools/src/newlib/newlib/libc/reent/closer.c:53: warning: warning: close is not implemented and will always fail/cygdrive/c/altera/72/nios2eds/bin/nios2-gnutools/H-i686-pc-cygwin/bin/../lib/gcc/nios2-elf/3.4.1/../../../../nios2-elf/lib/mno-hw-mul/pg//libc.a(lseekr.o)(.text+0x2c): In function `_lseek_r':/build/nios2eds-gnutools-win32-7.2/bin/nios2-gnutools/src/newlib/newlib/libc/reent/lseekr.c:58: warning: warning: lseek is not implemented and will always fail/cygdrive/c/altera/72/nios2eds/bin/nios2-gnutools/H-i686-pc-cygwin/bin/../lib/gcc/nios2-elf/3.4.1/../../../../nios2-elf/lib/mno-hw-mul/pg//libc.a(openr.o)(.text+0x2c): In function `_open_r':/build/nios2eds-gnutools-win32-7.2/bin/nios2-gnutools/src/newlib/newlib/libc/reent/openr.c:59: warning: warning: open is not implemented and will always failInfo: (hello_led_0.elf) 56 KBytes program size (code + initialized data).Info:                   16327 KBytes free for stack + heap.Hardware simulation is not enabled for the target SOPC Builder system. Skipping creation of hardware simulation model contents and simulation symbol files. (Note: This does not affect the instruction set simulator.)Build completed in 11.766 seconds

后来才明白在工程system library  properties 里面把lightweight device drive API勾掉就好了。