Passing a pointer parameter for DLL

[ZhuoCao]

Hi Guys:

I am little lost on how to execute below for my call library function node, please give me your best shot and thank you in advance:

GetHardwareInfo

This function takes a pointer to an array of bytes which will be loaded with three values:

1. I2C frequency (note that the value returned is the I2C frequency divided by 2)

2. 3.3V Power Output State (0 = ‘On’ and 1=’Off’)

3. 5V Power Output State (0 = ‘On’ and 1=’Off’)

C/C++:
int GetHardwareInfo(uchar *HardwareData);

Regards,

Joey

[James_R]

GetValueByPointer.xnode

C:\Program Files (x86)\National Instruments\LabVIEW 2012\vi.lib\Utility\importsl\GetValueByPointer

[nathand]

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@ZhuoCao wrote:

GetHardwareInfo

This function takes a pointer to an array of bytes which will be loaded with three values:

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An array of bytes is an array of 8-bit values (U8 or I8). Configure the Call Library node for that parameter as an array of U8, passed by Array Data Pointer.

[ZhuoCao]

Hello:

How do I pass the (uchar *Hardwaredata) into the DLL?  It is suppose to be a pointer value, I am not sure how to set it up.  What value do I connect to it in the block diagram, is it a string input?

 

[Bublina]

Hi,

For more, go : Help - Find examples, then Search, type DLL and open Call DLL example !

[nathand]

No need to typecast to a string, just pass the array directly:

[Bublina]

Or some other of those many methods left 🙂

[ZhuoCao]

Thanks for all the support guys, unfortunately I tried both methodologies and still having error 1097 for passing the string pointer and the u8 array pointer. See below, am I missing anything else?  I made two queries to the DLL and able to get the correct values back so I know I am connected to the DLL.

[Bublina]

Do you have the function code, especially the part where it operates the input *uchar ?

[ZhuoCao]

No I don't, I will contact vendor below and see if I get more details on the function call.

http://www.i2ctools.com/products.html