Lagrange Point famicom cart remake

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byemu
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Lagrange Point famicom cart remake

Post by byemu » Tue May 10, 2016 7:12 pm

I want to make a famicom Lagrange Point , It's finished now.
But no VRC7 sound.

Image

Image

lidnariq
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Re: Lagrange Point famicom cart remake

Post by lidnariq » Tue May 10, 2016 7:36 pm

Are you using a VRC7, or a CPLD (with a YM2413)?

The VRC7's audio output is extremely quiet, and uses a separate amplifier. Additionally it requires a separate clock source.

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byemu
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Re: Lagrange Point famicom cart remake

Post by byemu » Tue May 10, 2016 7:46 pm

lidnariq wrote:Are you using a VRC7, or a CPLD (with a YM2413)?

The VRC7's audio output is extremely quiet, and uses a separate amplifier. Additionally it requires a separate clock source.
I use a cpld, not VRC7.
Is it possible to use a YM2413+CPLD to full simulator a VRC7?

lidnariq
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Re: Lagrange Point famicom cart remake

Post by lidnariq » Tue May 10, 2016 8:32 pm

Sorta.

The YM2413 is the same electrical interface as the VRC7, but it sounds noticeably different. See the two audio recordings comparing the two sounds (left/right, each file is a different song) on our wiki.

On the other hand, if you just want in-tune bleep bloops, it's adequate. But if you just want in-tune bleep bloops you may be able to emulate just VRC7's ADSR acting on some square waves and fit that in a CPLD.

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byemu
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Re: Lagrange Point famicom cart remake

Post by byemu » Wed May 11, 2016 5:11 am

lidnariq wrote:Sorta.

The YM2413 is the same electrical interface as the VRC7, but it sounds noticeably different. See the two audio recordings comparing the two sounds (left/right, each file is a different song) on our wiki.

On the other hand, if you just want in-tune bleep bloops, it's adequate. But if you just want in-tune bleep bloops you may be able to emulate just VRC7's ADSR acting on some square waves and fit that in a CPLD.
Thank you.
I will try to add a normal YM2413 to my cart first.

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mikejmoffitt
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Re: Lagrange Point famicom cart remake

Post by mikejmoffitt » Thu May 12, 2016 6:41 pm

With the CPLD you may be able to do a lookup table to remap instruments. You won't be able to fully cover all cases, but certainly some of the YM2413 presets can be made closer than the ones they map to presently.

That said, it doesn't sound too bad with YM2413, just different.

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byemu
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Re: Lagrange Point famicom cart remake

Post by byemu » Fri May 13, 2016 6:07 am

mikejmoffitt wrote:With the CPLD you may be able to do a lookup table to remap instruments. You won't be able to fully cover all cases, but certainly some of the YM2413 presets can be made closer than the ones they map to presently.

That said, it doesn't sound too bad with YM2413, just different.
I'm just a primer, could you show more details on here.

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