APPENDIX B
Common PEN*KEY 6000 Series Information
PEN*KEY
R
6200/6300 Hand-Held Computer Programmer’s Reference Guide B-25
In the PEN*KEY 6000 Series system, shown in Figure BĆ4, the RAM disk stores
Windows and the application, along with data from the application.
1MB FLASH
System
Memory
DOS / BIOS
Windows
Application
Work Space
4MB
3MB
2MB
1MB
PCMCIA
SRAM
OR
FLASH
ÁÁ
ÁÁ
ÁÁ
ÁÁ
ÁÁ
ÁÁ
Figure BĆ5
PEN*KEY System with PC Card
In Figure BĆ5, a PC Card is used in place of the RAM disk. The system considers
the PC Card as a disk drive. There are several types of RAM and flash PC Cards
that can be used in this configuration.
Standard Mode Versus Enhanced Mode
Windows can run in either
standard
mode or
enhanced
mode. The enhanced
mode, better known, was created by Microsoft to provide
virtual DOS boxes
,
which make it possible for Windows to run DOS programs within the Windows
environment. Virtual DOS boxes insulate DOS programs from the hardware, in
essence simulating a DOSĆmanaged PC. The main drawbacks to enhanced mode
are slower execution speed and larger code size. Despite its name, the enhanced
mode is the
slower
of the two modes; and the size of the Windows code required
to support enhanced mode is up to 1 MB larger.
The standard mode, which is the native mode for Windows, does not support
DOS programs. But the standard mode is significantly faster and smaller than
the enhanced mode. Normally, the PEN*KEY 6000 Series Computer runs in
standard
mode only. This means that you cannot utilize both a DOS application
and a Windows application in the same environment on the computer. If WinĆ
dows is running on the PEN*KEY 6000 Series Computer, all applications must
be Windows applications. If DOS applications are needed, the PEN*KEY 6000
Series Computer should be operated in the DOS environment. For the applicaĆ
tion developer, this is critical. Some existing applications may require enhanced
mode to run; this is probably because of the following:
1. Applications were originally designed to run under DOS and were later
ported to Windows.
2. Applications make use of the Windows 32Ćbit memory model.
B. Common PEN*KEY
6000 Series Info.
