Busybox.net/ is a quick download.

Version 1.20.2 is used here, at the bottom of the download page.

After downloading, unzip it:

The tar - JXF busybox - 1.20.2. Tar..bz2Copy the code

Compiled tests:

• Version 1.20.2 was compiled successfully
• 1.27.2 failed to compile
• Version 1.30.1 failed to compile

make
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Once compiled, busyBox is used to build the root file system.

First create a new installation directory fs_mini_mdev_test to install busyBox, then specify this directory to install busybox using the CONFIG_PREFIX environment variable:

make install CONFIG_PREFIX=/home/ubuntu/busybox/fs_mini_mdev_test
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Once the installation is complete, there is a directory for basic commands in the installation directory, as shown in the following figure:

First find the location of the cross editor:

echo $PATH
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Then go to the directory:

cdThe/usr/arm - Linux - toolchains4.4.3 / bincd.Copy the code

Find the library file used by the cross-compiler:

find -name lib
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Sys-root: sys-root: sys-root: sys-root: sys-root

• ./arm-none-linux-gnueabi/sys-root/usr/lib

• ./arm-none-linux-gnueabi/sys-root/lib

The contents of the etc directory depend on the program you want to run, so only three files are created in this tutorial:

• etc/inittab
• etc/init.d/rcS
• etc/fsttab

The init process creates other child processes from the inittab file, such as calling script files to configure IP addresses, attaching other file systems, and finally starting the shell.

• ① Create the etc/inittab file

Create an etc directory in the fs_mini_mdev_test/ directory, and then create an inittab file, as shown in the inittab file example in Busybox.

# /etc/inittab
::sysinit:/etc/init.d/rcS
console::askfirst:-/bin/sh
::ctrlaltdel:/sbin/reboot
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• ② Create the /etc/init. d/rcS file

Create this file in the etc directory, which is a script file to which you can add commands that need to be executed automatically to edit the following:

#! /bin/sh
mount -a
mkdir /dev/pts
mount -t devpts devpts /dev/pts
echo /sbin/mdev > /proc/sys/kernel/hotplug
mdev -s
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Add executable permission, otherwise the startup will prompt no permission:

sudo chmod +x init.d/rcS
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Network adapters are not supported and IP addresses are not configured.

• ③ Create the etc/fstab file

The content of the file indicates the file system to be mounted after the mount -a command is executed. The content is as follows:

#device mount-point type options dump fsck order
proc    /proc   proc    defaults        0       0
tmpfs   /tmp    tmpfs   defaults        0       0
sysfs   /sys    sysfs   defaults        0       0
tmpfs   /dev    tmpfs   defaults        0       0
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Other directories can be empty. Run the following command to create them:

cd fs_mini_mdev_test/
mkdir proc mnt tmp sys root
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sudo apt-get install mtd-utils
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Reference tutorial: uboot study notes | uboot 2012.04 to 10 – transplantation JZ2440 (burning the Linux kernel, burning yaffs2 filesystem).

Download the file system image to the Windows host, save it to the TFTP server directory, and then use uboot to burn nand Flash in the development board:

tftp 30000000 fs_mini_mdev_test.jffs2
nand erase.part filesystem
nand write.jffs2 30000000 260000 678c24
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Then set the environment variable:

Set bootargs console=ttySAC0,115200 root=/dev/ mtdBlock3 RootFstype =jffs2 saveenvCopy the code

Restart the development board and test whether it can be mounted successfully:

reset
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