Intermec Janus 2010, User Manual, Page: 117 / 558

Learning About the Software
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3
Deciding How Much Memory to Use for RAM Drives
The size of the RAM drive you create is limited only by the amount of
extended memory in the reader. You can create multiple RAM drives as long
as the sum of their sizes does not exceed the amount of memory available.
Decide how much memory you will use for the RAM drive or drives:
Up to 256K
If you use up to 256K, all applications have enough memory to
operate normally. Intermec recommends that you adhere to a 256K limit.
From 256K to 320K
If you use more than 256K but less than 320K, the IRL
Desktop and IC.EXE run slowly because the RAM drive is using memory these
applications use for caching.
More than 320K If you use more than 320K, Reader Services cannot run. For
help deciding if you need Reader Services, see “Using Reader Services in
Applications” later in this chapter.
Creating a RAM Drive
You create RAM drives with the SRAMDISK.SYS device driver. Because
SRAMDISK.SYS works only in extended memory, the reader must be running
an XMS extended memory manager, such as HIMEM.SYS. Your CONFIG.SYS
must include a command that installs the memory manager before the
command that creates the RAM drive. For example, the default CONFIG.SYS
contains these commands in this order:
device=d:\himem.sys
device=d:\sramdisk.sys 256 512
When you create a physical RAM drive, DOS gives it the next available drive
letter on the reader. For example, if you create two RAM drives, DOS may
assign them drives E and F. In this case, the reader’s Type I PC card drive is
assigned drive G (instead of F) and the Type II PC card drive is assigned
drive H (instead of G).
To create or change a RAM drive
1. To create or change a RAM drive, you must edit the reader’s CONFIG.SYS
file, which is on drive C. For help, see “Learning How to Change the
Contents of Drive C” earlier in this chapter.
2. Verify that HIMEM.SYS or another XMS extended memory manager is
loaded into memory by a command in the reader’s CONFIG.SYS file.
3. Add a SRAMDISK.SYS command in the CONFIG.SYS file for each RAM
drive you want to add. The SRAMDISK.SYS command(s) must appear
after
the command that loads the extended memory manager.