Documents improvements

[TheDaChicken]

Deals with #346

It wasn't straightforward what the sample rate was meant to be for either of the 2 pipe functions. This adds macro and documents it for each function.

This also deals with a warning that Clion IDE gave me. It warned me that __declspec(dllexport) was meant to be used in the header. If needed, this part can be removed. This is a nick-pick. CMake newer versions can do this automatically using set(CMAKE_WINDOWS_EXPORT_ALL_SYMBOLS ON) though is not supported with this 2.8.

If you think of other constants that should be added, let me know.

My program has a simple #define NRSC5_MPS_PROGRAM 0x0 constant. Not sure if that is worth adding. It is simple zero.

[argilo]

This also deals with a warning that Clion IDE gave me. It warned me that __declspec(dllexport) was meant to be used in the header. If needed, this part can be removed.

If you don't mind, I'd rather consider that in a separate PR.

[TheDaChicken]

This also deals with a warning that Clion IDE gave me. It warned me that __declspec(dllexport) was meant to be used in the header. If needed, this part can be removed.

If you don't mind, I'd rather consider that in a separate PR.

Alright, I created, #350!

[argilo]

Looks good now. I'll merge once CI is happy.

[TheDaChicken]

Also a few things before merge:

Are you sure that it decimates only 2 from cs16? What about AM? There is DECIMATION_FACTOR_AM in acquire.c and also looks like it decimates by 32 in nrsc5.c

Should there be an NRSC5_PACKET_SAMPLES constant to prevent the 2048 magic number in main.c?

[argilo]

Are you sure that it decimates only 2 from cs16? What about AM? There is DECIMATION_FACTOR_AM in acquire.c and also looks like it decimates by 32 in nrsc5.c

That's a good point. For AM, there are five cascaded decimators, so the CS16 sample rate is 1488375 / 32 = 46511.71875. It would make sense to have separate constants for FM and AM.

Should there be an NRSC5_PACKET_SAMPLES constant to prevent the 2048 magic number in main.c?

Yes, I think that would be nice. They are called audio frames in the specification, so perhaps the name could be NRSC5_AUDIO_FRAME_SAMPLES.

[TheDaChicken]

Are you sure that it decimates only 2 from cs16? What about AM? There is DECIMATION_FACTOR_AM in acquire.c and also looks like it decimates by 32 in nrsc5.c

That's a good point. For AM, there are five cascaded decimators, so the CS16 sample rate is 1488375 / 32 = 46511.71875. It would make sense to have separate constants for FM and AM.

Should there be an NRSC5_PACKET_SAMPLES constant to prevent the 2048 magic number in main.c?

Yes, I think that would be nice. They are called audio frames in the specification, so perhaps the name could be NRSC5_AUDIO_FRAME_SAMPLES.

Alright. Those have been added!