Tag Archives: emulator

Cowon Emulator status

This post is mainly for my self, if you don’t have the basic understanding of how to make UCI’s for the Cowon this post wont make much sense.
I’ve been busy at work lately, so I haven’t really gotten as far as I wanted on my Cowon J3 & S9 emulator. But I’ll write a quick status update here and which problems I’ve encountered.

As it turns out, my understanding of how the device worked was very limited, and some of what I knew turned out to be wrong. My main fault was not understanding how the launcher.swf worked. It turns out that I only need to implement the ext_fscommand2 functions and not the functions starting with “gn_” (I found references to this function in some decompiled UCI’s). The “gn_” functions are in the launcher.swf which I simply load from the emulator (I had implemented about 25% of the launcher.swf in my emulator before I realized this :().

I’ve also figured out how I will make the file listing, or I’m down to 2 ideas. Both ideas include an AIR application that reads the device folders (which is going to be fun because I’ve never made an AIR application before).
The first solution (the one I’ll probably end up using), will have the application save an XML file with the folder and file structure. This XML is then loaded by the emulator and used to mimic the file system, requiring a manual update of the filesystem every time a file is changed (but like on the actual device the files don’t change that often).

After I get the filesystem up and running, it should be rather easy to emulate the actual playing of an MP3. But then again I thought a lot of the things that caused trouble in this project would’ve been easy.

Another thing I’ll give it a week or to and see if I get started up on the emulator again, if I don’t I’ll just release it in it’s current form, so you can see how it works for yourself. The current form however is a not to well documented and still in progress, set of classes with no actual UI everything I change I do code time.

Cowon J3 (Cow’n’Emu)

So I’ve recently bought the Cowon J3 32gb mp3 player. It’s a small upgrade from my Cowon S9, which was the 16gb version.

Both players has an excellent sound quality, the best I’ve ever had in an mp3 player (I’ve owned a couple of different ones, Rio, Creative, iPod, Samsung and something that starts with F that I can’t remember the name of anymore).
My only problem with the 2 Cowons is the touch-screen user interface, which has gotten a lot better with the J3. The problem is, even though the touch UI is improved, the new button(buttons on the actual device) layout is not as good as it was with the S9 (my own opinion).

But to the point of it all. Both the S9 and J3 runs on a Adobe Flash UI, and Cowon have opened up for their API, so you can make your own UI with flash and Actionscript 2 (unfortunatly the UI runs on a AVM 1 in Flash Player 7, so you can’t use AS3).
So I started out making a simple SWF to test out what the J3 was capable of, and how to use the Cowon API. And everything was really straight forward, to call their API you use the ext_fscommand2 function, and passed along some arguments letting the device know what you want to do.
The main problem is the testing phase. You need to plugin the player, transfer your SWF to it, plug it out, turn it on and then test it. The first couple of times it wasn’t an issue, but the 5th time you do it, it gets annoying, and the 10th time I did it, I stopped. It was to much of a hassle. So I searched the net for an emulator so I could test my project right away.
Now the only emulator I could find had no download link, and no one seemed to update it. So I decided to start working on my own.

So far I’ve implemented the ext_fscommand2 function and have it working as intended. But I haven’t made any actual functionality that simulates the device yet. One of the things I’m still having a hard time with is the Key events. I need to catch all the events from the UserSWF (the SWF you wish to load onto the device), and handle them in my own emulated environment instead of having Flash doing it for me.

Anyway, that was a long post just to tell you that I had started work on a Cowon S9+J3 emulator. Hopefully I’ll have a running alpha version next time I post about the subject.