EM-1240-LX User’s Manual | Software Package |
EM-1240-LX Software Architecture
The pre-installed µClinux Operating System used by the EM-1240-LX follows the standard µClinux architecture, making programs that follow the POSIX standard easily ported to the EM-1240-LX by using the GNU Tool Chain provided by www.uClinux.org. In addition to the Standard POSIX API, device drivers for the buzzer, and UART for the serial ports are also included.
The EM-1240-LX’s Flash ROM has more than one smaller partition, which contain the Boot Loader, Linux Kernel & Root (/) File System Image, and User Directory partitions.
For most applications, users often spend a lot time maintaining the operating system and modifying the system configuration. In order to save on the total cost of development and maintenance, the EM-1240-LX is specially design to partition a “User Directory” for storing the user’s system configuration parameters.
The EM-1240-LX has a built-in mechanism that prevents system crashes, helping preserve system reliability. The procedure is as follows.
When the Linux kernel boots up, the kernel mounts the root file system and then enables services and daemons. The kernel also looks for the system configuration parameters via rc or inittab.
Normally, the kernel uses the User Directory to boot up the system. The kernel will only use the default configuration _etc & _home when the User Directory crashes.
The EM-1240-LX uses ROMFS for the Linux kernel image, Root File System, and Protected configuration, and uses JFFS2 for the User Directory.
