July 30, 2020 at 12:13 PM #40180
I’m having quite a bit of issues getting my OSSC working for a PS2 with my setup. The PS2 is hooked up to the OSSC through component with HDMI output.
I use a 27 inch 1920×1080 PC monitor and can’t get a 4:3 aspect ratio/resolution. It’s like, maybe, 3:2? Definitely looks stretched. I’m almost positive it has to do with settings like “h.samplerate” or “h.backporch”. I’ve seen that for a PS2 the h.samplerate should be 686. The problem is, when I try to lower the sample rate or change various other settings, my screen goes black and loses signal. The only way to get it back is to reset settings. I’m adjusting them under the “Advanced Timing: 480i”, which I’m not sure if that’s even where I should be adjusting settings. For reference, I believe the default h.samplerate is 848 and default h.backporch is 40 something (don’t remember exact number).
I’ve spent a lot of time fooling with this device, and I’m clearly pretty inexperienced with it, so any assistance would be greatly appreciated.
Thank you!July 30, 2020 at 2:09 PM #40187ZacabebParticipant
The most universal sample rate for the PS2 is the standard DTV 858 samples/line for 60 Hz and 864 samples/line for 50 Hz.
An H.samplerate of 686.4 for 60 Hz (or 691.2 for 50 Hz) is theoretically optimal for games that have a horizontal resolution of 512 pixels, which includes a lot of PS2 games but not all. However, the display is likely to treat the resulting output as having square pixels, stretching the picture by 25%.
If the monitor accepts the picture when in Line4x mode, you’re likely to get the best results with that, with H.samplerate set to 858 and the Allow upsample2x mode enabled. Note that the picture is probably still going be a little wider than in Line2x mode (10% or so).
Edit: The default H. synclen is 62 and the default H. backporch is 57, in 480i mode.July 30, 2020 at 2:48 PM #40193
Thanks for the response!
Forgive me for my ignorance when it comes to this subject. Trying to understand.
I was under the impression that lowering the h.samplerate would basically shrink the width of the image/create larger black bars on the left and right of the screen, allowing the 4:3 aspect ratio without distorting the image quality. But it seems lowering the samplerate would actually stretch the picture?
Then, for line2x vs line4x: line2x is already too wide compared to a normal 4:3 aspect ratio, and my understanding based off what you said is that line4x would make it even wider. So I definitely wouldn’t want that if that’s the case.
I might be missing something though. It just seems like with my setup, there’s really no way to get the 4:3 aspect ratio. I’ve heard of optimal timing profiles from FirebrandX, not sure if they’re worth looking into.July 30, 2020 at 3:39 PM #40197ZacabebParticipant
You are right; lowering the sample rate should indeed narrow the picture.
My reference to the 686.4 samples/line is that it specifically targets the PS2’s 512 pixel resolution, and that wouldn’t be helpful in this case.
You can try using NTSC square pixels timings and see if they work with your display. They don’t match the PS2’s pixel clock at any of its resolutions, so the picture won’t be pixel perfect, but in Line4x with Allow upsample2x enabled it should still produce a very sharp picture with the same aspect ratio you’d get on a TV from the PS2.
H. samplerate: 780
H. synclen: 58
H. backporch: 59
H. active: 640
V. synclen: 3
V. backporch: 16
V. active: 240
The sampling phase setting can be ignored in this case.July 30, 2020 at 4:40 PM #40201
Okay thanks, that makes sense about the 686.4 samplerate.
I’ll try those settings that you listed, and report back if they work.
I have serious doubts they’ll work, because it seems that adjusting the samplerate anything below 840 causes my monitor to lose signal. No clue what could be causing that, if it’s my specific monitor or what. And I don’t know if I’ll have luck in line4x compared to line2x, like I’ve been using. I’ll be able to check after work.
I really appreciate your help!
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