Flash Storage; Ffs Partitions; Working With Ffs Partitions - Motorola MK4000 MicroKiosk Product Reference Manual

5 - 18 MK4000 MicroKiosk for CE .NET 5.0 Product Reference Guide

Flash Storage

In addition to the RAM-based storage standard on Windows CE devices, the MK4000 also includes a non-volatile
Flash-based storage area which can store data (partitions) that a cold boot cannot corrupt. This Flash area is
divided into two sections: Flash File System (FFS) Partitions and Non-FFS Partitions.

FFS Partitions

The MK4000 includes two FFS partitions. These partitions appear to the MK4000 as a hard drive that the OS file
system can write files to and read files from. Data is retained even if power is removed.
The two FFS partitions appear as the following two separate folders in the Windows CE file system:
•
Platform: The Platform FFS partition contains Motorola-supplied programs and Dynamic Link Libraries
(DLLs). This FFS is configured to include DLLs that control system operation. Since the MK4000 needs
these drivers for basic operation, only experienced users should modify the content of this partition.
•
Application: The Application FFS partition stores application programs needed to operate the MK4000.

Working with FFS Partitions

Because the FFS partitions appear as folders under the Windows CE file system, you can read and write to them
like any other folder. For example, an application program can write data to a file located in the Application folder
just as it would to the Windows folder. However, the file in the Application folder is in non-volatile storage and is not
lost on a cold boot (e.g., when power is removed for a long period of time).
You can use standard tools such as ActiveSync to copy files to and from the FFS partitions. They appear as the
Application and Platform to the ActiveSync explorer. This is useful when installing applications on the MK4000.
Applications stored in the Application folder are retained even after a cold boot.
There are two device drivers included in the Windows CE image to assist developers in configuring the MK4000
following a cold boot: RegMerge and CopyFiles.
RegMerge.dll
RegMerge.dll is a built-in driver that allows making registry edits to the Windows CE Registry. Regmerge.dll runs
very early in the boot process and looks for registry files (.reg files) in certain Flash File System folders during a
cold boot. It then merges the registry changes into the system registry located in RAM.
Since the registry is re-created on every cold boot from the default ROM image, the RegMerge driver is necessary
to make registry modifications persistent over cold boots.
RegMerge looks in the root of two specific folders for .reg files in the following order:
\Platform
\Application
Regmerge continues to look for .reg files in these folders until it checks all folders. This allows folders later in the
list to override folders earlier in the list. This way, it is possible to override Registry changes made by the Platforms
partitions folders. Take care when using Regmerge to make Registry changes. The DCP contains examples of .reg
files.
NOTE Regmerge only merges the .reg files on cold boots. A warm boot skips the merge process.