OSSC scanning wrong resolution?

[Spitko]

First off, as I’ve seen it in other threads, this isn’t about the number OSSC’s LCD shows. This is about the actual image. Note the example below, letters in certain columns look particularly bad, but most show some signs of being sampled off-target. These fonts should all be pixel perfect, with no alpha channel.

Not sure what to make of this honestly. It looks like it’s trying to do some kind of crazy linear interp across the screen; which implies to me it’s sampling pixels at the wrong resolution. I tried adjusting the sampling phase, but it just “moves” which pixels are sampled wrong. Nothing seems to correct the core problem.

System resolution: 512×512 ( Sharp X68030 )
OSSC reports 568p @ 31.5kHz / 55.46Hz
Sample2x OFF
Line2x ON
Tried resetting to default as well

[Harrumph]

You should set upsample2x to ON, it will then sample at double resolution horizontally.

[Spitko]

That does appear to fix the issue, is that simply necessary for x68k? The documentation seems to imply the default (off) would produce a 1:1 representation of the source image.

[paulb_nl]

With 568 lines the OSSC will choose the X68k 640×512 resolution at 800 samplerate. For pixel perfect sampling of 512×512 you have to change the sample rate at the advanced timing tweaker and adjust sampling phase.

It will be easier if you can get it to display a checkerboard pattern.

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