How to read BMP085 in LabView?

Hello,
I have a project which includes readings from barometric pressure sensor using LabView ONLY.
I searched for such component and the only one that I found with a reasonable price was the BMP085 (DataSheet_BMP085).
The problem is that I could not manage to understand how this component can be read in LabView, I found few examples in C++ but could not understand them enough to convert the code to LabView.
(Example)
My questions are:
- I have 2 ways of communication with this component:
1. RS232
2. Digital module through cDAQ (DI/O: NI_9403), which one is prefered for this purpose?
- Could anyone explain how the code should be written, or just if it's not too much of an effort to write a simple code for this application?
Thanks.

A serial port cannot be used as an I2C without some converter. Maybe there's one out there. But you might want to check out the I2C/SPI USB modules by NI. Their API is pretty easy to use as well.
USB-8451
USB-8452
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dr8086 wrote:
This method sounds like an excellent suggestion, but I do have a few questions where I dont think I've understood fully.
From what I understand the basic premise is to use one call library function node to access a DLL which creates an instance of the device object, and passes a pointer too it into labview. Then a seperate call library function node would pass this pointer to another DLL which could access the device object, update it and read the data. This part could be in a while loop and carry on reading the data until a stop command is given.
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extern "C" __declspec(dllexport) int __stdcall init(uintptr_t *ptrOut)
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return 0;
extern "C" __declspec(dllexport) int __stdcall get_data(uintptr_t ptr, double vals[], int size)
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extern "C" __declspec(dllexport) int __stdcall close(uintptr_t ptr, double last_vals[], int size)
int r= ((CDevice*)ptr)->close();
((CDevice*)ptr)->get_data(last_vals, size);
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// h file
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class CDevice
public:
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int init();
int get_data(double vals[], int size);
int close();
// only called by new thread
int ThreadProc();
private:
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vhtTrackerEmulator *tracker;
HANDLE hThread;
double buffer[500];
int buffer_used;
bool done; // this HAS to be protected by critical section since 2 threads access it. Use a get/set method with critical sections inside
//cpp file
DWORD WINAPI DeviceProc(LPVOID lpParam)
((CDevice*)lpParam)->ThreadProc(); // Call the function to do the work
return 0;
CDevice::~CDevice()
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My main concern is that the object may go out of memory or be deallocated, since it wouldnt be held in any namespace or anything.
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I also have a more general programming question about the purpose of the buffer. Would the buffer basically be a big table of position values, which are stored until they can be read into the rest of the VI?
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However, depending on the frequency with which you need to collect data from the device you might not need this buffer at all. I.e. if you collect a sample about every 100ms then you could remove all threading and buffer related functions and instead read the data from the read function itself like this:
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