PCMCIA cards are supported in Windows NT 4.0, but only with some important restrictions:
Installation of a PCMCIA card requires 5 steps:
Under some circumstances, the PCMCIA card may be detected by Windows NT and shown by PC Card (PCMCIA) applet, but the operating system nevertheless fails to allocate hardware resources for the card. (If this happens, the LayGO device driver will fail to start with an "insufficient resources" error which will be posted to the system event log.) To check whether this has happened, use the regedt32 utility to examine the Registry key:
If this key is missing or does not contain a
value for the PCMCIA card you are trying to install, the card was not assigned any hardware resources and
cannot be operated. Microsoft Knowledge Base article
HOWTO: Add PCMCIA Support to a Windows NT Device Driver explains how to use
Registry overrides to manually assign resources to the PCMCIA card. See the
Using a Registry Override section below for details on entering override values
in the Registry. If you have any questions about using Registry overrides, contact
technical support at
Advanced Relay Corporation.
Under some circumstances, the PCMCIA card may be detected by Windows NT and allocated resources by the operating system, but the card nevertheless does not work. The problem in these cases is usually the IRQ assigned to the card. There are 2 different situations:
In either case, some manual configuration is required. A Registry override (explained in the section above) can be used. Also, Microsoft Knowledge Base article Q168303: Masking IRQ's for PCMCIA Devices explains how to use the Registry to set which IRQs can be assigned to PCMCIA cards. Consult your PC manufacturer's documentation on IRQ steering for details on how to enable IRQs for use by "legacy" ISA bus devices. If you have any questions about IRQ configuration, contact technical support at Advanced Relay Corporation.
The Registry entries in laygontx.reg include a service entry for Laygontx1 in addition to that for Laygontx. (This entry is at the very end of the file.) It contains inactive Registry override values for the PCMCIA card (Pcmcia is set to 0). For instance, for the Advanced Relay PCMCIA cards, the entry look like this:
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LaygontF1\Parameters] "Pcmcia" = dword:00000000 "IoLength" = dword:00000008 "InterruptNumber" = dword:00000007 "IoBaseAddress" = dword:00000300
To use an override, edit this file with a text editor such as notepad. Change the InterruptNumber and IoBaseAddress values to those of the resources you have assigned. (The values are given in hexadecimal notation.) Change the Pcmcia value to 1 to enable the override. Save the file. To write the entries into the Registry, simply double-click the file name in Windows explorer. Do not change the hardware values in any other section of the file.