Problem using the FTDI library

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I keep trying to compile this code but the compiler keeps saying "invalid conversion from const void* to void*". I put library and header files in the right directories. i'm not sure what i'm missing. here's the code

C++

#include<windows.h>
#include<ftd2xx.h>
#include<iostream>
using namespace std;
int main()
{
	FT_STATUS ftStatus;
	FT_HANDLE ftHandle;
	ftStatus = FT_OpenEx("FT232R USB UART",FT_OPEN_BY_DESCRIPTION,&ftHandle);
	if (ftStatus == FT_OK) 
	{
		cout << "it worked!" << endl;
	}
	else 
	{
		cout << "it didn't work! : ( " << endl;
	}
	return 0;
}

In the FTDI driver folder, there's also some .sys files and .dll files. I wasn't sure what to do with them so I copied them to the program folder.

Posted 3-Jul-12 13:57pm

Taylor H

Updated 3-Jul-12 17:05pm

v2

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Jochen Arndt · Answer 1 · 2012-07-03T21:16:00

The first parameter of FT_OpenEx is of type LPVOID to pass different types (integer and char *) according to the second parameter. So you must use casting:

ftStatus = FT_OpenEx((LPVOID)"FT232R USB UART",FT_OPEN_BY_DESCRIPTION,&ftHandle);

If the FTDI DLL is present on your system (it is installed to the system folder when installing the device), all you need are the header file ftd2xx.h for including and the library ftd2xx.lib for linking.

barneyman · Answer 2 · 2012-07-03T14:34:00

Solution 1

The .lib files you have should also be part of the linker process; just add the .lib files into the VC project hierarchy (via Add Existing File)

Posted 3-Jul-12 14:34pm

barneyman

Comments

Taylor H 3-Jul-12 21:05pm

i tried making a project and doing that but it didn't work. originally i've been writing this as a single file. also, it will give me the object file but not the executable.

barneyman 3-Jul-12 21:11pm

looks like it requires GCC - the .a file should be the static lib for using the dll, in which case the .a file should be on the link list too, using GCC

Taylor H 3-Jul-12 21:38pm

okay, I'm gonna try that out right now! thanks for checking that out!

Taylor H 3-Jul-12 22:31pm

the driver i downloaded doesn't have a .a file. the one i downloaded is called d2xx. also, the program compiles when i exclude ft_openex line

barneyman 3-Jul-12 23:06pm

I just had a look at the windows download from 20824 - the ftdxx lib in the static/i386 dir exports that symbol

Taylor H 3-Jul-12 23:11pm

what does that mean? i tried using that one but it didn't work :/
do you know if i should be doing anything special with the dll and/or sys files?

barneyman 3-Jul-12 23:24pm

hmmm - curioser and curioser ... if you look at the DLP example they use GetProcAddress to get to all the dymbols

I'm sorry I can't be more use

Taylor H 3-Jul-12 23:35pm

that's okay! i downloaded one of the examples on that link, it's working. so i'll just carefully change that and see what happens. thanks!