PSS ID Number: 196122
Article Last Modified on 10/21/1999
The information in this article applies to:
- Microsoft Win32 Device Driver Kit (DDK) Windows 98
This article was previously published under Q196122
SYMPTOMS
PCMCIA devices that install properly under Windows 95 may fail to install
under Windows 98.
The device fails to start and Device Manager shows error code 7.
CAUSE
Under Windows 98 PCMCIA IRQ sharing is enabled only by default for Modem-
class devices. When Pccard.vxd's Enumerator Handler receives a
CONFIG_FILTER message, it performs the following checks:
- In the device's hardware registry branch, is "Class" equal to "Modem"?
- In the device's software registry branch, is "EnableIRQSharing" set to a
nonzero value?
If either of the above conditions is true, PCCARD allows the device to
share IRQs. However, if both conditions are false and the device has an IRQ
descriptor with the fIRQD_Share flag set, PCCARD fails the CONFIG_FILTER
message causing Device Manager to show error code 7
(CM_PROB_FAILED_FILTER).
RESOLUTION
To explicitly enable IRQ sharing, add a registry value named
"EnableIRQSharing" with a nonzero value in the device's software registry
branch. For example, in an inf AddReg section you could use the following
line:
HKR,,EnableIRQSharing,1,01,00,00,00
STATUS
This behavior is by design.
Keywords: kbprb KB196122
Technology: kbAudDeveloper kbWin32DDK98 kbWin32DDKSearch kbWin32sSearch kbWin98search kbWinDDKSearch