Symbol PTC-870IM, Руководство пользователя

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Memory
The PTC-870IM has two types of memory: read-only
memory (ROM) and random access memory (RAM).
ROM
The PTC has 2 megabytes (MB) of read-only memory.
The first 256 kilobytes (KB) are used to store
programs and information the PTC needs when it
starts up. These include the MS-DOS operating
system and the Basic Input/Output System (BIOS).
The remainder is available to hold the pen operating
environment, utility and device drivers, and an
application program. If your PTC has a radio, 64
additional KB of ROM are installed to hold the radio’s
control program.
The documentation provided with
the Telxon Pen-based 11x4 Series
Software Development Kit contains
details on reprogramming flash
EPROMs. The PTC’s ROM is contained on electronic chips called
flash EPROMs, which can be reprogrammed while
inside the PTC. This makes it easy to update the
operating system and your application program when
necessary.
The advantage of having these programs in ROM is
that they will remain loaded in the PTC even when it
is rebooted. In this way, ROM acts much like a disk
drive (ROMdisk) as far as the PTC is concerned.
Refer to the “Drive lettering” section on page 29 for
the drive letter assignments.
RAM
The PTC’s standard configuration has 2 MB of
random access memory. (4-, 8-, and 12-MB options
are also available.) RAM is used to store data the
PTC needs while it is running. One MB of RAM is
reserved for running the operating system and your
application. The remaining RAM can be used by
applications or as a RAMdisk (random access memory
emulating a disk drive).
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