WinCEGeräteSE_Handbuch_Programmierung_v3.00_EN
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1.1.4 System startup
After switching on the device, the keyboard controller activates the voltage supply of the processor module.
The steps described below are then executed.
a) Starting the boot loader
The boot loader initializes the registry and sets internal processor states. The boot loader searches for boot
scripts (autoboot.bat) on the (optionally integrated) SD card and on locating a script, it will execute the script.
If it does not find an SD card, it executes the processor module’s autoboot.dat saved in the NAND flash.
b) Setting the display parameters and displaying the boot image
The autoboot.bat boot script in the CPU module NAND flash copies the display parameters to the processor
in a command line sequence and activates the display output.
A boot image (boot.bmp) is part of the file set for the SD card and is installed into the NAND memory when
the OS is flashed so that it can load the boot script with a regular start. The image is displayed during the
rest of the booting process.
c) Loading and starting the OS kernel
The NAND boot script file autoboot.bat then extracts the nk.nb0 kernel into the RAM memory. The entry
point of the CE kernel is initiated and Windows CE initialises.
In the memory division of the persistent registry, a search starts for a valid registry signature. If this
signature is found, the data is copied to the RAM and used as the current registry. Changes are not copied
automatically back into the flash; this process has to be initialised explicitly (“Save Registry”).
If no valid registry is found, the default registry saved in the OS image is used instead.
Windows creates a ROM file system where the Windows files are mirrored. It is also possible here to create
other files in the file system that are then stored in the persistent flash file system.
Drivers for Windows (e.g. snmp), that are to be integrated later by the monolithic kernel, can be stored in the
\windows or \flashdisk\drivers folders.
d) Launching ACD system services
After initialisation, the kernel launches some ACD system programs. These are saved persistently in the
memory (e.g. the “status bar” or the scanner data insertion). A dynamic start screen (GuiCmd) visualises
the startup and automatically hides the desktop until the user program is fully initialised (see also Chapter
6.5) so that users cannot access the system during startup.
The StartConfig tool is used to define which functions are available in the device (see the administration
documentation).
Shortly after startup, important system parameters are displayed on the desktop to quickly guide users
through the OS.