Appendix C PC Card Questions and Answers
National Instruments Corporation C-3 DAQCard E Series User Manual
by Card Services and/or the memory manager. Second, you can attempt
to determine all of the memory that Card Services can possibly use and
then exclude all but that memory from use by Card Services.
2. How do I determine all of the memory that Card Services can use?
One way to find out which memory addresses Card Services can use is
to run a utility such as
MSD.EXE
that scans the system and tells you
how the system memory is being used. For example, if you run such a
memory utility and it tells you that physical addresses C0000 to C9FFF
are being used for ROM access, then you know that C8000–D3FFF is
an invalid range for Card Services and should be changed to CA000–
D3FFF.
3. How can I find usable I/O addresses?
Identify usable I/O addresses by trial and error. Of the three resources
used—memory, I/O, interrupts—I/O conflicts will be low. You can use
WDAQCONF
in Windows to diagnose I/O space conflicts. When you
have configured
DAQCONF
or
WDAQCONF
for a particular I/O space,
save the configuration. If there is a conflict, the configuration utility
will report an error describing the conflict.
4. How do I find usable interrupt levels?
Some utilities, such as
MSD.EXE
, will scan the system and display
information about what is using hardware interrupts. If you have such
a utility, you can run it to determine what interrupts Card Services can
use. Card Services needs an interrupt for itself as well as one interrupt
for each PCMCIA socket in the system. For example, in a system with
two PCMCIA sockets, at least three interrupts should be allocated for
use by Card Services.
Keep in mind that utilities such as
MSD.EXE
will sometimes report that
an interrupt is in use when it really is not. For example, if the computer
has one serial port, COM1, and one parallel port, LPT1, you know that
IRQs 4 and 7 are probably in use. In general, IRQ5 is used for LPT2,
but if the computer does not have two parallel ports, IRQ5 should be
usable. IRQ3 is used for COM2, but if the computer has only has one
serial port, IRQ3 should be usable.
5. I run a memory utility, and it appears there is no memory available for Card
Services. What should I do?
You should remove your memory manager by commenting it out of the
CONFIG.SYS
file. Next, you can rerun the memory utility. Memory