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Documentation Number PCRTC2095 Manual
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5105
Chapter 3. Operation
Overview
The most common application of the PCRTC is to simply
maintain the correct time on the host computer. Loading the device
driver in the CONFIG.SYS file will accomplish this function by
setting the DOS clock to the PCRTC clock time once every minute.
This allows the user and all applications access to the correct time
without any special commands or function calls.
The PCRTC has two additional features which may either
be incorporated using the provided “include file” and making
function calls within your program, or from the command line using
the PCRTC.EXE file. The first of these functions is battery status. By
checking the battery status you can take action on a low battery
before the time is corrupted. The second function is the time of last
power loss or reset. By checking this function, the time of the last
host computer power loss or system reset can be determined.
Using the Device Driver
In order for the PCRTC to automatically update the DOS
clock, the device driver PCRTCDD.SYS must be loaded from
CONFIG.SYS. This is done automatically by the installation
program. The following line will be added to the CONFIG.SYS file:
DEVICE = {path}PCRTCDD.SYS /A:{hex PCRTC address}
For example, if the file PCRTCDD.SYS is in the directory
C:\PCRTC, and the card address is set to 200h, use the following
line.
DEVICE = C:\PCRTC\PCRTCDD.SYS /A:200
If the address 200 is not compatible with your hardware, the
address parameter must be changed to match the address that was
selected for the hardware. After modifying the CONFIG.SYS file,
reboot the host computer. If the hardware and driver are installed
correctly, you should see the following message during bootup.