Symbol PDT 3400 Series, Руководство по продукции

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4-1
Chapter 4
Terminal Configuration Issues
Memory Available Versus Program Requirements
The PDT 3400 memory configuration required depends on the operating system or systems
and the application(s) you intend to run on the terminal.
Configuration Options
The terminal’s on-board RAM and on-board Flash configuration determines what software
can be loaded on the terminal. Configuration options of up to 4.5 MB of Flash, and up to 4
MB of RAM are available.
On Board RAM
Up to 4 MB of RAM is available for a RAM disk on the PDT 3400. One option for increasing
the amount of RAM available is to use the compression utility Stacker, which is included with
the PDT 3400 SDK. Based on a compression rate of 1.8 to 2.5, Stacker can expand a 0.5 MB
RAM disk up to 1.25 MB.
On Board Flash
Up to 4.5 MB of on-board Flash is available for the PDT 3400. To obtain more “disk”
storage, one alternative is to use Stacker.
The amount of on-board Flash required depends on what you plan to load into “ROM disk”.
Some possibilities are DOS, applications, and other user files. On-board Flash is divided into
“segments”, with segment divisions falling on 64K or 128K boundaries (refer to Figure 4-1).
It is not possible to update a portion of a segment; the full segment must be updated as a unit.