ftd2xx | Python library around FTDI D2XX Looking for new maintainer

I do have a solution and it works with barebone code provided in the Flutter-Desktop-Embedding project which I assume you used for your desktop application. You are on the right track but just need some finalisation.

For testing, I used this simple c code with several functions to test passing the pointers, returning pointers, filling memory, allocation and deallocation. This is the C code I used in my dll.

The error is caused by symbols exported with __declspec(dllimport) in header files that can't be imported from a shared library (.DLL).

I would recommend creating a libftd2xx.dll.a file from the ftd2xx.dll file and linking with that (e.g. if the files are in the current directory using -L. -lftd2xx.dll).

Or you could probably just link with the .dll file by specifying it in the gcc command, something like this: gcc -o test.exe test.c HPX-Windows.c ftd2xx.dll -g).

If that doesn't work check ftd2xx.h to see where __declspec(dllimport) is imported and see if you can set a define that causes the header to not use __declspec(dllexport)/__declspec(dllimport) and link with your lib file in case it's a static library (something like: gcc --static -o test.exe test.c HPX-Windows.c -L. -lftd2xx -g).

Assuming this is python:

You can index each individual byte in the byte array with []

my_buffer = bytearray(d.read(1024)

now my_buffer[0] holds the value of the first byte in your byte array, represented as an integer with value 0-255. You will need to additionally cast this integer to a character to create a character array / string. ASCII is the typical correlation between an integer value and its character representation. The order of the bytes in your FIFO buffer is dependent on what is putting bytes into the FIFO on the not-USB side of the FT232. Many devices send data most-significant first, but you should verify this against that device's data sheet.

The FT_HANDLE is an output parameter in FT_OpenEx. You are correctly passing &ftH so that the function can overwrite ftH.

The FT_HANDLE is an input parameter to the other functions. You are incorrectly passing &ftH and should pass just ftH.

FT_Close(&ftH); FT_Close(ftH);

Unfortunately FT_HANDLE is defined in a loosely-typed way:

Solved.

There's a bug in the 2.34.50.20200227 i686-w64-mingw32-ld.exe. It won't work with ftd2xx.lib, regardless of ftd2xx version as far as I can tell.

2.25.51.20150320 and 2.29.1.20171006 work with ftd2xx.lib. I've reverted back to 2.29 mingw64-i686-binutils. I'm running again.

Possible you have to install approciate version of C++ Redistribatable for your FTDIVCPLIB.dll. On machine with VS2019 your have already had it.