Meinberg DCF77PC32 - Manual (Page 15)

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The resident driver for DOS/Windows
The resident driver PCPSDRV.COM runs with DOS version 2.11 or greater and
Windows 3.x. It uses only about 1100 bytes of memory and periodically synchronizes
the computer´s system time to the board time. Additionally, the driver is able to
display the board´s time continuously in a window on the text screen. This feature can
be enabled and controlled by some of the utility programs (see next chapter).
In order to avoid conflicts accessing the board the driver should not be installed or
be temporarily disabled using the utility DRV.EXE if user-written software accesses
the board.
If the driver has to be installed every boot time, it should be called from the
AUTOEXEC.BAT which should reside in the root directory of the boot drive. Assu-
ming the driver file can be found in the directory MEINBERG on drive C:, a
command line like that shown below should be added to the AUTOEXEC.BAT using
any text editor:
C:\MEINBERG\PCPSDRV [port addr] [U:xxxx] [I] [R]
The parameter port addr must be given if the board has been jumpered to use an
alternate port address instead of 300 hex.
The optional parameter U:xxxx can be used to set the time span to be used for the
periodical update of the system time. Valid numbers for xxxx are 1 to 3600 (seconds).
If this parameter is omitted the time span defaults to 1800 seconds (= 30 minutes).
The parameter I must be given in the command line if the driver shall modify the
computer´s time just after being installed. In the default case the computer´s system
time will only be modified when the clock has synchronized at least once after power-
up (Status: Synchronized after last Reset). If the clock has to work in an electrically
noisy environment or with very low RF signal it can´t synchronize very often and it
could be recommended that the computer´s time is synchronized with the PC32´s time
before the clock has synchronized with DCF77 (the PC32 offers a more exact time
than the computer´s system time even when running on XTAL).
The last parameter R tells the resident driver to set the real time clock in AT
compatible computers directly. This is only required if the DOS/BIOS interrupts
which modify the computer´s time are redirected by other applications as on Novell
Netware 2.xx file servers. In the default case this parameter should not be used in
order to minimize the execution time of the resident driver.