Picodrive: Skipping Fmv On Mega Cd Games

[Duddyroar]

I've noticed that FMV MCD games in PicoDrive skip quite a bit. Now I'm aware that this is highlighted as a potential problem but is there any way around it? I've tried bumped the cache up which solves the skipping, but then the emulator obviously has to pause every few seconds to fill up the cache memory each time, so it's even worse than the skipping.

Is this an SD card issue? Are there any super-fast SD cards that get around this problem? Or has anyone tinkered with the settings and discovered the 'sweet' spot that solves this problem?

 

[namco]

Just wondering, but is that cache double buffered?

Would it be possible to implement or would that hamper performance?

 

[Duddyroar]

Personally I have no idea, perhaps one of the more technical minded chaps can help?

 

[sbock]

There is no known solution for this problem. The SD port of the GP2x is very slow (and DMA brokern per design from the chipset manufacturer). Faster SD cards wouldn't change this.

Regards,
Stephan

 

[notaz]

I've noticed that FMV MCD games in PicoDrive skip quite a bit. Now I'm aware that this is highlighted as a potential problem but is there any way around it?

Smaller capacity cards are often faster. My 512MB SanDisk card runs those games noticeably better than 4GB A-data SDHC.

Just wondering, but is that cache double buffered?

Would it be possible to implement or would that hamper performance?

What do you mean by double buffered? There is a single buffer with read-ahead data (when enabled).

There is no known solution for this problem. The SD port of the GP2x is very slow (and DMA brokern per design from the chipset manufacturer). Faster SD cards wouldn't change this.

Well faster cards help a bit, I have confirmed that. Also, it might be possible to work around the problem somehow (Exophase posted some ideas), I'll try experimenting a bit more.

 

[fusion_power]

I've never thought, the SD Acess of the GP2X is THAT Slow. I have 2 San Disk SD's (1GB and 2GB) and booth can do 5MB/sec and above onto my PC with Card Reader. But it can't play the entire "SONIC CD" Intro without skipping onto the GP2X. I think we can be happy that at least the mp3's are playing without trouble. :lol:

Isn't it possible to load the ENTIRE Video into the Ram of the GP2X before the Video starts? Or load as much as possible and keep reloading, if the big starting-buffer is empty...? (currently it feels like the buffer doesn't refill while video is playing) At least for short Videos like Sonic CD Intro - and Endings!? Anything that makes it possible to see the whole thing without interruption? I want to show some people the Game and the Videos...but not with the "commercial breaks" in it

Sonic Boom, Sonic Boom, Sonic Boom
Trouble keeps you runnin' faster
Sonic Boom, Sonic Boom, Sonic Boom
Save the planet from disaster...
:lol:

 

[imhotep]

Also, it might be possible to work around the problem somehow (Exophase posted some ideas), I'll try experimenting a bit more.

Awesome. I hope you find something.

 

[namco]

QUOTE

What do you mean by double buffered? There is a single buffer with read-ahead data (when enabled).



Like as the video is being played from one buffer, more data is read into another buffer, and the process flips over then the first buffer has finished playing the video segment from the first buffer?

 

[WhiteFalcon]

QUOTE

What do you mean by double buffered? There is a single buffer with read-ahead data (when enabled).

Like as the video is being played from one buffer, more data is read into another buffer, and the process flips over then the first buffer has finished playing the video segment from the first buffer?


I guess what notaz describes is a circular buffer. Double buffering would hardly do any good as the speed of drawing the frames would outrun the speed of loading them from the SD card anyway. No gain afaik.

 

[Duddyroar]

notaz - Awesome, thanks for listening to my problem! The emulator is fantastic in every other way aside from this, it's easily my most-used emulator on the GP2X!