Metrologic IS4910 Series, Руководство программиста

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IS4910 D
EVICE
D
RIVER
Registry Settings
The registry settings allow to load and to configure the driver. The driver must be properly configured on
the target device in order to work properly. For that purpose the driver reads the configuration parameters
from the registry during loading. The driver’s registry values must be stored under the
[
HKLM\ RootKey \ DriverKey ] key, where RootKey is a string value defined under the [ HKLM\Drivers ]
key and DriverKey is an arbitrary string which names the driver dedicated subkey. If the RootKey is not
defined, it defaults to Drivers . But traditionally RootKey is Drivers\BuiltIn . The name of the driver’s
subkey is arbitrary, but it should be unique among the direct subkeys of [ HKLM\ RootKey ]. For example
good choice for the DriverKey is IS4910 .
The following table shows the relevant registry values under the driver’s subkey. First four values in the
table are the basic entries used by the Device Manager under Windows CE in order to load the driver.
And the other values are the driver-specific entries used to configure the driver and initialize its operating
parameters.
Value Type Description
Prefix STRING
Defines the three-letter name of the driver. Must be VUQ . The
device name is constructed from the Prefix value appended the
Index number.
Dll
STRING
Specifies the name of the DLL that implements the driver
(
vuqdrv.dll )
Index DWORD
(Optional) Defines the instance number of the device and can be
a single decimal digit starting from
1 (first instance) to 9 (ninth
instance) and 0 (tenth instance). The Index number is appended
to the Prefix value to construct the device name. Default is 1 .
Order DWORD
(Optional) Specifies the order in which the driver should be
loaded and ranges from
0 through 255 . The drivers with lower
Order values are loaded before drivers with higher Order values
in the registry.
SysIntr DWORD
(Optional) Specifies the system interrupt number corresponding
to the quick capture interface IRQ. If it’s not defined the driver
would request the IRQ-to-SYSINTR mapping.
DMAChannel
DWORD
(Optional) Specifies the DMA channel to be used by the driver
for DMA operations. If it’s not defined then the first found free
DMA channel would be used.
MaxMemFrames DWORD
(Optional) Specifies the maximum number of frames the image
buffer can hold. Default is 4.