Psion Teklogix Vehicle-Mount Computer 8590 - Manual (Page 149)

8580/8590 Vehicle-Mount Computer User Manual 123
Chapter 8: Internal Devices
Drivers
8.6.2 Drivers
DLoGPwrw.sys driver V1.0 for Windows XP
Standard setting: I/O port 0x379, length 2 Bytes
The 8580/8590 and the automatic shutdown module communicate via the
motherboard control port, which consists of the two I/O ports described above.
8.6.3 General Notes About Automatic Shutdown Software
The Config program must be installed for the automatic shutdown module to
function correctly.
If the Config has not been started, the 8580/8590 will carry out a hard shutdown
once the delay time and shutdown time set by the hardware has elapsed. In this case,
the operating system is not shut down normally before the power is switched off.
The current application is unable to save its data, and the file system becomes
increasingly unstable and inconsistent.
If the Config has been started, the program can recognize when the operating system
needs to be shut down. Firstly, the Windows message
“WM_QUERYENDSESSION” is sent to all running applications to inform them of
the impending shutdown.
Now every application has to respond within the time that is set in the registry. If a
response is not sent in the specified time, the application is forced to quit.
If there are any open programs with unsaved changes, it may not be possible to
automatically quit them (for example, an unsaved document in WORDPAD.EXE, a
program supplied with Windows). In this case WORDPAD.EXE responds to the
Windows message “WM_QUERYENDSESSION” with a user query to confirm if
the current file is to be saved. Applications that can be quit with the key combination
[ALT] and [F4] (that is, without a final user query) generally send the required
response to the “WM_QUERYENDSESSION” message and are not shutdown
“hard”.
To ensure that vital data is always saved correctly, applications need to be able to
properly respond to the “WM_QUERYENDSESSION” message, that is, without
user queries and within the set time period.