关于调用 GlobalMemoryStatus API函数的问题

我在一个标准模块中申明了:
Public Declare Sub GlobalMemoryStatus Lib "kernel32" (ByRef lpBuffer As MEMORYSTATUS)
Public Type MEMORYSTATUS
dwLength As Long
dwMemoryLoad As Long
dwTotalPhys As Long
dwAvailPhys As Long
dwTotalPageFile As Long
dwAvailPageFile As Long
dwTotalVirtual As Long
dwAvailVirtual As Long
End Type

在窗体模块中有一个按钮,按钮的事件如下:
Private Sub Command1_Click()
GlobalMemoryStatus MEMORYSTATUS
End Sub

当单击按钮时,会出现: ByRef argument mismatch 的错误,不知道怎么解决???