Picodrive Vsync

[lnx64]

Just got the Caanoo, and am notcing that PicoDrive doesn't VSync very well.. On the Wiz it was amazing, be it a 60 or 50Hz game it played silk smooth even with VSync off.

On the Caanoo, especially when playing a sonic game, it seems to be a little on the choppy side, like the VSync is turned off.. It's not tearing, but it's like frames are being skipped.. My Caanoo came with firmware 1.6.0 btw if that helps..

 

[notaz]

On Wiz the LCD refresh is set to multiple of game refresh (100/120Hz), on Caanoo it's not. I haven't searched for such timings, and nobody else did at the time of release. In case those timings are known (haven't seen them yet), they can be set in PD launch script.

 

[DaveC]

Just got the Caanoo, and am notcing that PicoDrive doesn't VSync very well.. On the Wiz it was amazing, be it a 60 or 50Hz game it played silk smooth even with VSync off.

On the Caanoo, especially when playing a sonic game, it seems to be a little on the choppy side, like the VSync is turned off.. It's not tearing, but it's like frames are being skipped.. My Caanoo came with firmware 1.6.0 btw if that helps..

I have noticed this while using Temper on the Pandora too. The scrolling gets choppy. I know it isn't the emu.

Is there a way to fix or set something to fix that?

 

[lnx64]

On Wiz the LCD refresh is set to multiple of game refresh (100/120Hz), on Caanoo it's not. I haven't searched for such timings, and nobody else did at the time of release. In case those timings are known (haven't seen them yet), they can be set in PD launch script.

I wouldn't know how to do that. Isn't the LCD in the Caanoo 60Hz? That's what I was told and was one of the reasons I purchased this console. Only to find now that PicoDrive (my main intent emulator) doesn't even sync to the screen.

 

[lnx64]

Oh please someone make a fix for this in the startup script. I don't know programming or anything like that. I just want to game, that's all, and game nicely.

 

[lnx64]

I made an interesting discovery. PAL games nearly run silk smooth, only skipping a frame every half second. So, that makes it seem that the LCD is more closely tied to 50Hz it seems.

Does that mean then that the LCD refresh rate can't be changed then from what I understand above since no one has timings?

 

[CKeichel]

I made an interesting discovery. PAL games nearly run silk smooth, only skipping a frame every half second. So, that makes it seem that the LCD is more closely tied to 50Hz it seems.

Does that mean then that the LCD refresh rate can't be changed then from what I understand above since no one has timings?

The refresh rate on a TFT display can't be compared to a refresh rate on a CRT Monitor, because it is generated in a completely different way. On a CRT, the picture is generated by a beam, that "paints" it a certain ammount of times on the screen, on a TFT every pixel of the display can change it's appearance a fixed number of times per second. This means, the picture generation takes exact 1/60 second, while on a CRT the picutre is generated from the upper left to the lower right by the ray and the effect of a stable picture is supported bei the time the cathode tube emmits light after the beam hit it.
On an OLED display like the Wiz it is different as well, as far as I know, black pixels on an OLED display are indeed not active, other then on an TFT display, where they have a black "color". As far as I know a TFT always has a fixed refresh rate, that can't be changed and it's usually 60 Hz.

 

[lnx64]

That's not true, as I have worked in a repair shop for computer electronics. LCD's can in fact change refresh rates, in the means of changing their phase inversion speeds to co correspond to the refresh rate the incoming signal is. It's usually a range of 50-75Hz they are capable of taking.

 

[CKeichel]

That's not true, as I have worked in a repair shop for computer electronics. LCD's can in fact change refresh rates, in the means of changing their phase inversion speeds to co correspond to the refresh rate the incoming signal is. It's usually a range of 50-75Hz they are capable of taking.

Interesting, I didn't knew this, I always thought, they run with a fixed frequency, but you are right, even in Windows XP, I can change the refresh rate of my TFT and the info panel shows then the new refresh rate.

 

[lnx64]

Yea, it's how 1080p LCD's that do 24Hz even function.. Though they don't actually "do" 24Hz, they sample it 3 times to 72Hz and the panel actually does that. If the panel really did 24Hz, the phase inversion would be so slow that it'd almost seem grainy. And those 120 and 240Hz TV's, well, those are just insane, but they can do 60Hz also, or even 72Hz, it's in the menu for them..

I wish people knew about this more often. Sure a CRT has a beam that refreshes, but LCD's got phase inversion. On old LCD's, phase inversion was actually done in the same way of interlacing.. Those are "row phased" types.

As for the Caanoo though, I'm not sure if it can be changed, but by default, it seems to be close on the 50Hz side, and is stuck there.. Even in Quake, if you turn on FPS counter, and look at a wall, it maxes out at 50fps which backs it up even more..

 

[Berserk]

Even in Quake, if you turn on FPS counter, and look at a wall, it maxes out at 50fps which backs it up even more..

Is that with vsync enabled? If so, then that's probably the display's refresh rate. It might be worth testing fps in another app to verify.

 

[lnx64]

Is there any update on this? Will PicoDrive ever truly support a VSync for the Caanoo?

It's got me torn between my Wiz and Caanoo. I like the Caanoos sound quality, but I love the Wiz's smooth framerate on Picodrive..

 

[lnx64]

Damnit, I want VSYNC!!

This is seriously the only GP2X I know to NOT even try to have VSYNC in ANY application at all.

 

[lnx64]

Bump..

 

[lnx64]

I guess I will still bump this.