MiSTer FPGA Forum

Especially for Nigel Butterfield I have just done a pull request to add a "Space Invaders (Samples)" mra file that uses samples to implement the various sounds for it rather than the embedded code from the original SI core.

hopefully sounds more like the real thing with these.

Oh yes you have sir and I am not even Nigel !

Could you please advise how can I get this ?

...also...

...is it possible to somehow have the artwork from Mame in the background as well ?

Grab it from github until it's merged.

https://github.com/MacroFPGA/Arcade-Spa ... r/releases

...is it possible to somehow have the artwork from Mame in the background as well ?

possibly ...

Awesome stuff!

Nigel approves and appreciates your efforts, wholeheartedly

Now added a background for SI as well, normal and sample versions.

macro wrote: ↑Sun Nov 28, 2021 11:17 pm Especially for Nigel Butterfield I have just done a pull request to add a "Space Invaders (Samples)" mra file that uses samples to implement the various sounds for it rather than the embedded code from the original SI core.

hopefully sounds more like the real thing with these.

Just to feed my curiosity, what is the benefit of doing this ?

Gave this a spin last night. The game works fine and the samples sound great, but whilst within the OSD menu, the screen constantly flickers on and off.

Forgive me if this is a noob question but if I add this mra will update_all download the samples & backgrounds? Thanks

mario64 wrote: ↑Tue Nov 30, 2021 1:45 am Forgive me if this is a noob question but if I add this mra will update_all download the samples & backgrounds? Thanks

the mra contains the background and samples, so you don't need to update-all as well. (or just use update-all to get the mra in the first place)

Fallon wrote: ↑Tue Nov 30, 2021 1:03 am within the OSD menu, the screen constantly flickers on and off.

all the invaders core based games (that I tried) do it, something to do with the pause in menu I guess. You would have to submit a bug report.

Does the mra with samples and background use more than 32MB SDRAM?
I have no problem with the version without sample but with the version with samples I can only add coins, after that all other buttons are ineffective. These 2 versions use the same config files and no one complained about the version with samples, this is the reson I suspect SDRAM size.

macro wrote: ↑Tue Nov 30, 2021 10:23 am

mario64 wrote: ↑Tue Nov 30, 2021 1:45 am Forgive me if this is a noob question but if I add this mra will update_all download the samples & backgrounds? Thanks

the mra contains the background and samples, so you don't need to update-all as well. (or just use update-all to get the mra in the first place)

Thank you so much! I got the update and tried it out. The sounds are obviously much more accurate now but I get audio only from the left channel. There is no right channel audio at all. Any idea why?

Curious if this sample approach will make it to Space Invaders Part II, the fire sound is a little rough as I recall..

Thank you Macro!

While it's nice to have authentic sampled chirps from the source, I think striving to faithfully replicate/improve on initial TI SN76477 chip implementation, would be in the best spirit of FPGA preservation.

Please don't get me wrong; I understand that'd be perhaps an impossible task, but Space Invaders is such a monumental stone to the form we call 'vidya' , that it'd be worthwhile and fulfilling to undertake (imho).

Now, let me take my coat

P.S. A personal nag, if you will: can you look at merging the latest framework feature (aka shadow masks) into your Space Panic core? It's one of my favorites (and it'll be the first arcade core to do so!).

Any idea why audio with this MRA is left channel only?

mario64 wrote: ↑Wed Dec 01, 2021 9:44 pm Any idea why audio with this MRA is left channel only?

yes, there's a line missing in samples.vhd

(which is odd since I thought I fixed it ages ago!)

sorting it out now, pull request done.

lamarax wrote: ↑Tue Nov 30, 2021 7:15 pm I think striving to faithfully replicate/improve on initial TI SN76477 chip implementation, would be in the best spirit of FPGA preservation.

Yes, I agree - it's just mathematically simulating the three separate waveforms (LFO, VCO and noise), applying the attack sustain and decay (all controlled by external voltage via capacitors and resistors), applying any feedback and any subsequent filters (the op amps) - all of which is now done by a comprehensive set of functions in Mame (which took Derek a long time to write!)

I've done some in cores where a sample just won't work, but it takes a long time to get there, especially if you wish to re-create it using integer math rather than full floating point (e.g. 280 zzap engine noise)

re-creating 10 noise circuits for one game just isn't high on my agenda of things to do!

(SC01 sound chip comes first, and that has about 23 dynamic filters to implement all in floating point)

lamarax wrote: ↑Tue Nov 30, 2021 7:15 pm P.S. A personal nag, if you will: can you look at merging the latest framework feature (aka shadow masks) into your Space Panic core? It's one of my favorites (and it'll be the first arcade core to do so!).

when I get time / do other updates, I use a real CRT, so not something I would use personally.

macro wrote: ↑Wed Dec 01, 2021 10:26 pm

mario64 wrote: ↑Wed Dec 01, 2021 9:44 pm Any idea why audio with this MRA is left channel only?

yes, there's a line missing in samples.vhd

(which is odd since I thought I fixed it ages ago!)

sorting it out now, pull request done.

Great thank you!