CHAPTER THREE - PL3000 BASICS
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hard-resetting with the power button varies a little bit according to the state in which
your device is. However, the point is to press the power button continuously at
least for ten seconds.
To hard-rest your device with the power button:
1. Press the power button and hold down it
2. Release the power button after holding down it for ten seconds
3. Repress the power button, the system reboots
Note
! Re-slotting the battery into its chamber does not necessarily reset
your device but typically generates just sleep/awakening cycle.
REGISTRY
The Windows Embedded CE running on the Nordic ID PL3000 has a database
used to store configuration information for the system itself and for applications.
The database also contains state information that the operating system continually
references during operation, so in general it is a channel to communicate between
different parts of the system in different operational states. The database is called
registry as in all versions of Windows. However, the layout of the Windows CE
registry does not match up with the Windows versions running on the desktop
machines.
On the PL3000 the implementation of the registry is RAM-based, meaning that
the Windows CE maintains the registry in its object store being a RAM-based file
system. This matter has consequences for the persistence of the registry keys and
values, if changed, deleted, or created. Although the RAM device on the PL3000 is
battery backed, meaning that the RAM is being refreshed when the device is
turned off, the registry data does not persists on cold boots, without mentioning the
hardware resets. It’s also possible that the device remains lying idle for long
enough so that all the batteries on the device run down and the registry settings
vanish. However, so called factory settings in the registry does not cease to exist
because the system image of the CE windows includes a file containing the registry
settings generated during the build process of the Windows CE image.
The Windows CE gives options to implement a save-and-restore method in
order to keep volatile registry changes persisting when the registry in the RAM is
erased (e.g. on the cold boot), or when the RAM device is not being powered. On
the PL3000, one of the save-and-restore methods is implemented so that the
contents of the RAM-based registry can be stored in a non-volatile memory, if need
be. The Windows CE system checks for the up-to-date registry information in the
memory during booting up, and if the updated registry file is available the system
initializes the registry database in the object store accordingly.
To store the changed registry information in the non-volatile memory there are
two options available on your device. One possibility is that your application calls a
