Software Registry Entries - Psion EP10 User Manual

Under the \driver subkey, add the following standard registry values for drivers:
• Prefix (REG_SZ)
• Dll (REG_SZ)
• Index (REG_DWORD)
• Flags (REG_DWORD)
• IClass (REG_MULTI_SZ)
For descriptions and details of these values, consult the Microsoft documentation on developing device
drivers. Note that the Order value is not used here.
The registry keys and values in the \driver subkey are not accessed directly, but are used as a template to
create a driver entry in a different registry location. The \driver subkey and all of its entries are copied to
the following registry location:
[HKLM\Drivers\BuiltIn\Peripherals\devices\active\4\[Device ID]
Note: The driver entries are only copied if the driver key is present and contains a Dll registry value.
The drivers for detected peripherals are loaded from this "active" registry location. The driver is loaded
through a call to ActiveDeviceEx() after other initialization is finished.
It may also be necessary to copy registry keys from one location to another in the registry before loading a
driver. To do this, first create a "RegCopy" subkey. For example:
[HKLM\Drivers\BuiltIn\Peripherals\devices\4\1\RegCopy]
Within the \RegCopy subkey, add one or more entries in the form of "source" = "dest", where source is the
source registry key and dest is the destination registry key.
Note: In the rare case that registry information needs to be copied outside HKEY_LOCAL_MACHINE,
instead name the subkey "RegCopy_HKCU" (for HKEY_CURRENT_USERS) or "RegCopy_HKCR"
(for HKEY_CLASSES_ROOT).
Remember that the backslash '\' characters in the registry key strings will need to be 'escaped' with
another backslash character. For example:
[HKLM\Drivers\BuiltIn\Peripherals\devices\4\1\RegCopy]
"Drivers\\BuiltIn\\Peripherals\\devices\\4\\1\\RegKeys" = "Software\\Psion\\DeviceDriver"
This function copies the specified source key and all subkeys underneath it to the target location.
In rare cases, multiple drivers may need to be loaded to support a single piece of hardware. In these cases,
the Windows bus enumerator can be used (see the Microsoft documentation at
http://code.msdn.microsoft.com/BusEnum2) . Alternatively, the driver specified in the driver key can load
the other drivers.
3.4.2

Software Registry Entries

If the peripheral uses custom software, the version information for the software can be added to the
System Properties of the System Control Panel applet.
Using the registry functions, create the following registry key (where <name> is the name of the software
component as it will appear in the System Properties):
[HKLM\Software\Psion\SystemProperties\Software\<name>]
Beneath that key, set the following registry values:
• @ (REG_SZ): Default value. Set to "Components" to make the software information appear in the Com-
ponents list of the System Properties.
• Value (REG_SZ): Enter the version of the software component here.
Chapter 3: Software
Software Registry Entries
Psion EP10 HDK User Manual
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