Symbol PDT 8000, Руководство по продукции

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Configuring the Terminal
downloading of an IPL causes permanent damage to the mobile computer. IPL is
mandatory for the mobile computer.
• Partition Table: Identifies where each partition is loaded in the mobile computer.
Downloading Partitions to the Terminal
TCM is used to specify a hex destination file for each partition and download each file to
the terminal. This download requires a program loader stored on the terminal. The terminal
comes with a program loading utility, Initial Program Loader (IPL), stored in the terminal's
write-protected flash.
IPL
IPL allows the user to upgrade the mobile computer with software updates and/or feature
enhancements.
Partition Update vs. File Update
There are two types of update supported by the mobile computer: partitions and files. The
file system used by the mobile computer is the same as the file system used on a desktop
computer. A file is a unit of data that can be accessed using a file name and a location in
the file system. When a file is replaced, only the contents of the previous file are erased.
The operating system must be running for a file to be updated, so the IPL cannot perform
individual file updates as it is a stand-alone program that does not require the operating
system to be running.
A typical partition is a group of files, combined into a single "partition" that represents a
specific area of storage. Examples of partitions are the flash file systems such as Platform
or Application. (Using the desktop computer comparison, these partitions are roughly
equivalent to a C: or D: hard disk drive.) In addition to the "hard disk" partitions, some
partitions are used for single items such as the operating system, monitor, or splash screen.
(Again using a desktop computer comparison, these partitions are roughly the equivalent
of the BIOS or special hidden system files.) When a partition is updated, all data that was
previously in its storage region is erased - i.e. it is not a merge but rather a replacement
operation. Typically, the operating system is not running when partitions are update, so IPL
can perform partition updates.
Partition images for selected partitions can be created by TCM. All partition images suitable
for use by IPL are in hex file format for transfer by TCM from the development computer to
the mobile computer.