Unitech MR650, Руководство по программированию

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2.2. Unregister the application from the USI.DLL
Function Description:
Unregister the application from the DLL. It will close the scanner port, and by default it will disable
the scanner.
Function call:
void USI_Unregister ();
Return code:
None
2.3. Enable / Disable Scanner
Function Description:
To starts or stop USI function. This function is useful for application to temporarily stop scanner
function if it is only need keypad input or keep clear input buffer.
Function call:
BOOL USI_EnableScan ( BOOL bStatus );
Parameter: (input)
bStatus: TRUE : Enable Scanner
msgID: FALSE : Disable Scanner
Return code:
BOOL: TRUE : OK
FALSE : Failure
2.4. Reset Scanner
Function Description:
Set the scanner to the working mode, and reset the communication control.
Function call:
BOOL USI_Reset ();
Return code:
Always TRUE
2.5. Get error code
Function Description:
Returns the error code (SERR_***).
Function call:
DWORD USI_GetError ();
Return code:
Return the error code (SERR_***), which has been described in USI_Register function.
2.6. Return the system error code
Function Description:
Return the system error code, which is returned by GetLastError. It will also return the description of
the error in buffer if it is not NULL.
Function call:
DWORD USI_GetLastSysError ( LPTSTR buffer , int len );
Return code:
Return the system error code, which is returned by system function GetLastError. It will also return
the description of the error in buffer retrieved by system function FormatMessage if it is not NULL.
For a complete list of error codes, refer to the SDK header file WINERROR.H.