Chapter
CIN Parameter Passing	2
This chapter describes the data structures that LabVIEW uses when
passing data to a CIN.

Introduction

LabVIEW passes parameters to the CINRun routine. These parameters correspond to each of the wires connected to the CIN. You can pass any data type to a CIN that you can construct in LabVIEW; there is no limit to the number of parameters you can pass to and from the CIN.

CIN .c File

When you select the Create .c File... option, LabVIEW creates a .c file in which you can enter your CIN code. The CINRun function and its prototype are given, and its parameters are typed to correspond to the data types being passed to the CIN in the block diagram. If you want to refer to any of the other six CIN routines (CINInit, CINLoad, and so forth), see their descriptions in Chapter 1, CIN Overview.

The .c file created is a standard C file, except that LabVIEW gives the data types unambiguous names. C does not define the size of low-level data types—the int data type might correspond to a 16-bit integer for one compiler and a 32-bit integer for another compiler. The .c file uses names that are explicit about data type size, such as int16, int32, float32, and so on. LabVIEW comes with a header file, extcode.h, that contains typedefs associating these LabVIEW data types with the corresponding data type for the supported compilers of each platform.

extcode.h defines some constants and types whose definitions may conflict with the definitions of system header files. The LabVIEW cintools directory also contains a file, hosttype.h, that resolves these differences. This header file also includes many of the common header files for a given platform.

© National Instruments Corporation

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LabVIEW Code Interface Reference Manual