FDSloadr "This is not an authentic FDS image"

[JessicaWolf]

So, I got myself a (free) laptop running Windows 95 just for the purpose of using FDSLoadr.

However, I continue to get the message "This is not an authentic FDS image" when trying to load images.

I can't seem to find a clear answer as to how to solve this issue. Can anyone offer any insight?

[Issun]

I think the FDS images need to have a 16 byte header for FDSLoadr to load them, so check your images. If they don't have one, you can add one via an hex-editor, the format can be found here: http://wiki.nesdev.com/w/index.php/Family_Computer_Disk_System

[JessicaWolf]

Ok, after fooling with it for a couple hours, and trying to fully understand everything, I just don't think I get it. Is there anyone out there who could offer help. The game I am trying to work with is Metroid (version 1.1), since I already own a copy but it just needs to be rewritten. Is there anyone who could so me an example of a proper header for this game?

[kiwidaveinjapan]

So, I'm actually sending you a copy of Metroid with the twin I posted you...

Did you read the guide attached to the bottom of my post in the "how to" question you posted? it shows how to edit the header.

Hope this helps.

[JessicaWolf]

I believe I have done that already, but maybe I did it in the wrong place?

Spoiler

[close]

[ericj]

That disk image is missing the header.

[JessicaWolf]

Is there anyone out there who could show me the proper header info for this disk?

I am not the best at reading this kind of code and such, but once I see it I can understand it much better.

[ericj]

Metroid should look like this:



What I usually do is open a good disk image with a hex editor, copy the header, and paste it into the file missing the header. The first line where you see 02 is for a 2-sided disk. Simply change this to 01 for a one-sided game.

[JessicaWolf]

You are amazing ericj, now I see where I screwed up and what you meant by there being no header.

Just out of curiosity, why does the header not get dumped when dumping a disk?

EDIT: Also, if it loads properly in an emulator, that means I did everything properly, right?

[Issun]

Just out of curiosity, why does the header not get dumped when dumping a disk?

Because that 16 byte header is not on the disk. It's just part of the FDS file format.