The SetClicks method examines all currently-enumerated HID devices, finds those with a Vendor-ID equal to NCR’s assigned Vendor ID (0x0404). Among all qualified devices found, each device is searched for a KEY_CLICK_INFO feature report that contains Volume, Frequency, and Duration usages. When a matching device is found, that device’s product ID (PID) is used to locate keyclick values within the Registry. The values found in the registry are sent to the device in the KEY_CLICK_INFO feature report.
Each time SetClicks is invoked, it reads Volume, Frequency, and Duration keyclick parameters from the registry. If these parameters are not found in the registry, default values are written to the registry, and these default values are used. This causes the registry to contain the values most recently sent to NCR HID KeyClick devices.
The default values for Volume, Frequency, and Duration, SetUsbKeyClick are 15, 1318, and 16, respectively.
The SetKeyMatrix method examines all currently-enumerated HID devices, finds those with a Vendor-ID equal to NCR’s assigned Vendor ID (0x0404). Among all qualified devices found, each device is searched for a KEYBOARD_MAP feature report that contains an array of KEY_MATRIX_USAGE usages, When a matching device is found, that device’s PID is used to locate Key Matrix entries in the Registry. If no Key Matrix values are found for that specific PID, no Key Matrix download is performed.
For each KEYBOARD_MAP device located, SetKeyMatrix creates a full default keyboard matrix that duplicates the factory-default matrix of the specific product located. Next, the registry is read for replacement values within the Keyboard Matrix. All registry values found in the appropriate registry key are replaced within the default matrix. Finally, the full key matrix as modified by registry values is sent to the keyboard using the KEYBOARD_MAP feature report.
