kernel module is the innermost core of the system. it has the highest security and is always protected by the system. only the failure of flash memory or improperly power off during system restart after updating kernel will the kernel be destroyed. the kernel module ensures that user can always download their own program even the operating system was crashed by user's program. it provides the following services:

    ·program download

    ·update kernel

    ·test & calibrate

    for detail operations, please refer to section 5.4.