Specifications

PERFORMING DOWNLOADS
Omni 37xx Download Differences
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MNI 37XX REFERENCE MANUAL 85
The Main Application is Always Stored in GID1
The main application stored in GID1 is the controlling application for the terminal.
Any function call that invokes a related program or a secondary application stored
in GIDs 2–14 must be initiated by the GID1 application.
An application stored in a file group other than GID1 is limited in that it can only
access executables and files stored in its own file group and in GID15.
Physical and Logical Access to File Groups
The Omni 37xx operating system controls
physical access to GIDs 1–15 using
password-protected system mode functions.
To download data into a specific file group, you must first enter system mode and
choose the target group by making the appropriate menu selections. Then, you
must enter the correct password for that file group.
Each file group has its own CONFIG.SYS file. The CONFIG.SYS settings of the
target group you select are always used as the system parameters for the
download operation you are performing.
The system of file groups also imposes some
logical restrictions on which files can
download into which file groups:
• If GID1 is selected as the target group in system mode, you can download files
into GID1 and redirect files into any of the other file groups, as required, in the
same download operation.
• If another file group is selected as the target file group, you can download files
only into that group and redirect files only to GID15. For example, if you select
GID5 as the target group for the download, files can only download into GID5
and be redirected to GID15.
Use of RAM and
Flash Memory
The Omni 37xx application memory partition has two separate file systems:
• RAM (battery-backed volatile memory, also called SRAM), drive name I:
• Flash (non-volatile memory), drive name F:
The fact that there are two different file systems has the following important
implications for data transfer procedures:
• Depending on the requirements of a specific application, some files must
download into RAM and others into flash.
• There are also rules that restrict which types of files you can download and
store in which file system (RAM or flash).
With application files, the application designer or programmer usually decides
which file types to download into which file system. Other file types, such as
operating system files, digital certificates, and signature files,
must download into
RAM.