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Zeviouz (2600)

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4 hours ago, Thomas Jentzsch said:

One could omit PF0 (which would look pretty odd then with the striped background) and save 14 cycles/scanline. And/or use two-line sprites and save 11 cycles/scanline. Maybe then it becomes feasible. But the overall conclusion is that you cannot replicate the Zeviouz kernel even theoretically using pure 6507 assembler.

Interesting. I think a Zeviouz-style background with two-line sprites wouldn't be a bad trade-off if someone wanted to attempt a non-ARM game done in a similar style, though.

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5 hours ago, Thomas Jentzsch said:

 

  • Displaying a sprite using e.g. MaskedDraw requires 11 cycles, that results into 22 cycles for both sprites.

 

You could use extra RAM here, and have a 256 byte array for each sprite, with the sprite shape.

Then the sprites code would be

 

  lda sprite1shape,y
  sta GRP0
  lda sprite2shape,y
  sta GRP1
  


That would be 14 cycles, I think, to do both sprites.

You could alternate scanlines for colour writes/shape writes, and have multicolour sprites, 14 cycles/ilne, 2 line resolution.

 

 

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5 hours ago, Andrew Davie said:

You could use extra RAM here, and have a 256 byte array for each sprite, with the sprite shape.

That would work, but it would require a lot of RAM and quite a lot of CPU time for moving the sprite data while scrolling. 

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11 hours ago, Thomas Jentzsch said:

But the overall conclusion is that you cannot replicate the Zeviouz kernel even theoretically using pure 6507 assembler.

 

If the kernel is executed from RAM then self-modifying code could be used to achieve the same effect in pure 6507.   This would require a lot of RAM for a full screen display, and the cost of all the writes would be prohibitive.   However, if DCP/DPC+ is permitted then I believe it becomes feasible with pure 6507 assembler?

 

For me, I'm comfortable using CDFJ and other techniques(e.g. bus stuffing)  to push the TIA to the limit :)

 

Chris

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37 minutes ago, cd-w said:

If the kernel is executed from RAM then self-modifying code could be used to achieve the same effect in pure 6507.  

That was part of my calculation above already. I suppose you think about a fully unrolled kernel which runs from RAM. That might work, but is far off the original hardware too.

 

37 minutes ago, cd-w said:

This would require a lot of RAM for a full screen display, and the cost of all the writes would be prohibitive.   However, if DCP/DPC+ is permitted then I believe it becomes feasible with pure 6507 assembler?

I think DPC is not fast enough too. But I am no expert here.

 

37 minutes ago, cd-w said:

For me, I'm comfortable using CDFJ and other techniques(e.g. bus stuffing)  to push the TIA to the limit :)

Sure, no problem with that. I was just checking the limits of the original hardware.

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10 hours ago, rhuneke said:

I can't select difficulty level. Only Intermediate is available. Is this option not yet enabled???

It works for me. Use the select switch to change the mode.

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I finally had a chance to download and play this. What amazing work! I love this. This was one of my favorite games in college and you've captured the feel of it so well. I look forward to seeing the mothership!

 

 

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I just finally played this via Harmony cart and just wanted to say how impressed I was....  I can't believe you were able to do such a faithful recreation on the 2600.

 

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Any news/updates about this? I‘m very excited about a PAL60 version and the other things you mentioned at the beginning 🤗

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I'm playing this via harmony on my 7800 using edladdins  Seagull adapter for using genesis controllers.
it only detects 1 button and checked it with my 7800 Xevios cart and two button works there with difficulty switch set to different setting.
I look for my prolines and see if will detect two buttons and get back to on it

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5 hours ago, Dan Iacovelli said:

I'm playing this via harmony on my 7800 using edladdins  Seagull adapter for using genesis controllers.
it only detects 1 button and checked it with my 7800 Xevios cart and two button works there with difficulty switch set to different setting.
I look for my prolines and see if will detect two buttons and get back to on it

Did you try using the Genesis controller on the 2600 without the adapter? The adapter is used to make the Genesis controller work like a 7800 controller, but I heard that it's not possible for the 7800 controller's second button to work in 2600 mode?

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6 minutes ago, BrianC said:

Did you try using the Genesis controller on the 2600 without the adapter? The adapter is used to make the Genesis controller work like a 7800 controller, but I heard that it's not possible for the 7800 controller's second button to work in 2600 mode?

I'll have to dig out my 2600 and try then thanks

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32 minutes ago, Dan Iacovelli said:

I'll have to dig out my 2600 and try then thanks

It should work on the 7800. Just plug the Genesis controller directly into the 7800.

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ok I tired with just controller plugged into the 7800 still nothing.  and tried my 2600 but it isn't working.
also when just put the  genesis controller in makes the harmony cart menu go crazy when I plug it in with edladdin seagull menu works  normal.
I'll figure something out for the first round of harmony games for the bonus game (ports are in the bonus games this year,orignal games play as normal games)
 

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3 hours ago, Dan Iacovelli said:

also when just put the  genesis controller in makes the harmony cart menu go crazy

You need to hold down the B button when powering on the console to have Harmony detect the Genesis controller. 

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20 hours ago, Karl G said:

You need to hold down the B button when powering on the console to have Harmony detect the Genesis controller. 

ok will check that out

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@Karl G

Thanks for the tip it was exactly that with the button on harmony cart. now I know the setting for Bonus game in round 1 of harmony games that I mentioned ZPH last night

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2021 Harmony Games have begun bonus(Ports)

we are using the current rom,if any updates happen during this round we will use that

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Posted (edited)

ZeroPage Homebrew is playing ZEVIOUZ for a high score in the Harmony Games on tomorrow's (Tue Mar 16, 2021) stream LIVE on Twitch at 6PM PT | 9PM ET | 2AM GMT! Hope everyone can watch!

 

 

Games:

 

 (SET VIDEO TO 1080P60 FOR FULL QUALITY)

 

 

 

Edited by ZeroPage Homebrew

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