Embedded System Setting up Development Environment Tool chain installation GCC tool chain includes gcc compiler,assembler, linker, and other related utilities. (root@host)#rpm –ivh armtools-2.95.3- 5.i386.rpm Add /usr/local/gnu-2.95.3/bin to the searching path. (root@host)# export PATH=/usr/local/gnu- 2.95.3/bin:$PATH Setting up Development Environment Installing uClibc (root@host)#rpm –ivh uClibc-0.9.5- 1.i386.rpm The uClibc will be installed in /usr/local/uClibc-0.9.5 Building busybox BusyBox: The Swiss Army Knife of Embedded Linux Official site: http://busybox.net Install the BusyBox Configure the function of busybox Modify Makefile make Configure the function of busybox Config.h // This file defines the feature set to be compiled into busybox. // When you turn things off here, they won’t be compiled in at all. // //// This file is parsed by sed. You MUST use single line comments. // i.e., //#define BB_BLAH // // BusyBox Applications //#define BB_ADJTIMEX //#define BB_AR #define BB_ASH … # If you are running a cross compiler, you may want to set this # to something more interesting, like “powerpc-linux-“. CROSS = arm-elf- CC = $(CROSS)gcc … CROSS_CFLAGS+= -nostdinc –I$(LIBCDIR)/include –I$(GCCINCDIR) #Add below LIBCDIR=/usr/local/uClibc-0.9.5/linux-2.0.x GCCINCDIR=/usr/local/gnu-2.95.3/lib/gcc-lib/arm-elf/2.95/include Modify Makefile # If you are running a cross compiler, you may want to set this # to something more interesting, like “powerpc-linux-“. CROSS = arm-elf- CC = $(CROSS)gcc … CROSS_CFLAGS+= -nostdinc –I$(LIBCDIR)/include – I$(GCCINCDIR) #Add below LIBCDIR=/usr/local/uClibc-0.9.5/linux-2.0.x GCCINCDIR=/usr/local/gnu-2.95.3/lib/gcc-lib/arm-elf/2.95 How to use busybox first # ln -s busybox /bin/utilyname # utilyname Second busybox utilyname Building uClinux O.S Build kernel Get kernel source code - kernel- 2.0.38.tar.bz2 http://www.kernel.org/pub/linux/kernel ftp://linux.csie.nctu.edu.tw/kernel Patch root@host:~/linux/ #patch –p1 < patch-uClinux- arm-2.0.38.gz http://www.uclinux.org/pub/uClinux/ Building uClinux O.S Use netstart-patch root@host:~/linux/ # zcat ../uClinux- NETStart-2.0.x.patch.gz | patch –p1 Set kernel configure make menuconfig (make xconfig) make dep && make clean make linux.bin Building an initial ramdisk image Build ramdisk: root@host:~/# dd if=/dev/zero of=/tmp/initrd1024 bs=1k count=1024 Format : root@host:~/# mkfs.minix /tmp/initrd-1024 Mount : mount -o loop –t minix /tmp/initrd-1024 /mnt/initrd Building an initial ramdisk image add/delete files into this directory bin/ dev/ proc/ lib/ etc/ mnt/ usr/ sbin->bin/ Building an initial ramdisk image umount umount /mnt/initrd dd if=/tmp/initrd1024 bs=1k count=1024 | gzip -9 /tmp/initrds.gz Download O.S to NET-Start! board Download O.S to NET-Start! board Download O.S to NET-Start! board Download O.S to NET-Start! board Download O.S to NET-Start! board System power up, the switch 2 of SW2 is set at the OFF position, the bootstrap loader will boot into the built-in Linux kernel. Commands of bootstrap loader HELP – Help UNIT - Set access unit DUMP - Memory dump COPY - Memory copy FILL - Fill memory POKE - Poke memory PEEK - Peek memory TX - Send XMODEM file RX - Receive XMODEM file GO - Execute binary INFO - Print system information Download O.S to NET-Start! board RUN>Help Download O.S to NET-Start! board download linux.bin to NET-Start! board RUN> rx 0x10000 RUN> copy 0x10000 0xb0000 0x1810000 download initrds.gz to NET-Start! board RUN> rx 0x10000 RUN> copy 0x10000 0x70000 0x18c0000 Developing Application Program Step1. Build the binary code root@host:~/ # arm-elf-gcc -c hello.c root@host:~/# arm-elf-ld -L/usr/local/gnu- 2.95.3/lib/gcc-lib/arm-elf/2.95.3 -L/root/uClibc/lib - L/usr/local/gnu/arm-elf/lib -elf2flt -o hello /root/uClibc/lib/crt0.o /usr/local/gnu-2.95.3/lib/gcc- lib/arm-elf/2.95.3/crtbegin.o hello.o /usr/local/gnu-2.95.3/lib/gcc-lib/arm- elf/2.95.3/crtend.o -lc -lgcc -lc 2 Developing Application Program Step2. download the program. Step3. Execute the program # chmod +x hello # ./hello Reference http://netcity3.web.hinet.net/UserData/st one369/comp/linux_one_disk.htm.