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Can I get away with flickering in a 160 pixel kernel?


ZackAttack
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I've been trying to leverage bus stuffing to create a 160x192 single color image with 30hz flicker. I've got it to the point that all but 4 columns are drawn using 30hz flicker. For the remaining 4 columns I can only fill in the gaps with the ball object. This unfortunately requires 15hz flicker for those 4 columns. My test bitmap doesn't exactly look great in stella and I'm waiting on some parts to arrive before I can test this on real hardware.

 

Do you think the 15hz flicker could be overlooked considering the potential for having a full 160x192 frame buffer to draw to?

 

post-40226-0-12197700-1446356111_thumb.png

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Interested to see results on real hardware. Are you out of missiles?

I remember experts remarking on clever use of missiles and the ball to fill gaps in large bitmaps...

 

Stella can glitch when banging the TIA with resets and player copies, etc. for these advanced effects.

Stella glitches on Space Rocks' text / name credit kernel. Hold both fire buttons down on both joysticks when powering on. I can do this on Stella with two connected wireless controllers, or you can set Stella on PC, Mac or Linix to start with different things.

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Originally I had 5 gaps, but I did fill one with a missile. The problem I'm having with doing that is that I'm using tripled players NUSIZ setting for both players and thus also both missiles. In the case where I did use the missile I had an extra write at just the right time to disable the missile before its 2 copies got drawn.

 

 

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Originally I had 5 gaps, but I did fill one with a missile. The problem I'm having with doing that is that I'm using tripled players NUSIZ setting for both players and thus also both missiles. In the case where I did use the missile I had an extra write at just the right time to disable the missile before its 2 copies got drawn.

 

 

Don't disable it, change its data and position...

Sorry, I'm not a programmer but I'm making suggestions.

Please forgive me if they are stupid or can't work due to timing / cycles.

 

I do have an understanding of how it operates and displays, and coming up with new things is fun and takes both creative and technical thought.

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I tried a completely different approach from scratch today and still I end up with 4 gaps. On the plus side the gaps are all close to the left side. So I could chop it off at the second gap and have around 130 pixels @ 30Hz.

 

Think I'm going to table this until I have the hardware to test with. That way I can be sure I'm not just fighting stella.

 

post-40226-0-68151900-1446435122_thumb.png

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So I've settled on repeating a 48 pixel pattern that does a good job of getting players on the screen in alignment with each other. The strange thing is that the left most players get hidden/shifted after the first scanline. I'm not really sure if stella is doing the right thing here. Assuming 2 characters per cpu clock and R0 G0 representing RESP0 strobe and GRP0 update respectively. The pattern looks like this:

......R0G1....G0......R1G0....G1

Here's one of the 2 frames. You can see the very top line looks correct. It only contains 8 pixel gaps and they are 16 pixels apart. The second line on has the hidding/shifting problem. I'm strobing HMOVE on cycle 73, RESP0 on 74 and reading a byte for the next instruction on 75. P0 is pink. P1 is blue.

 

post-40226-0-38575500-1446553435_thumb.png

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