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Derrick Renaud
Discrete Coder
Reged: 10/18/03
Posts: 438
Loc: The Local Pub
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Re: 74LS629
10/20/10 04:06 AM


> Can you elaborate for a non-engineer how the simulation / emulation of the sound is
> changing?

The old code was based on the data sheet, which are notoriously incorrect. The new code is based on testing the real IC. The old code generated frequencies that were too low. Lets say the real chip puts out 56kHz under certain conditions. The old code would only generate 30kHz. The new code generates 56kHz.

Or as Kitsune Sniper said: "Funny numbers make funny sounds."

D.


Do not p-mail me for help compiling my updates, ask on the board.
Do not request sound for your favorite game. I work on whatever, when I get around to it.
If you have schematics for discrete sound games not easily found on the net, I would be interested.







Entire thread
Subject Posted by Posted on
* 74LS629 Derrick Renaud 10/19/10 04:22 AM
. * How many games use the 74LS629? mike20599  11/07/10 02:37 AM
. * Re: How many games use the 74LS629? Derrick Renaud  11/07/10 06:29 PM
. * Re: 74LS629 StilettoAdministrator  11/05/10 10:15 PM
. * Phenomenal and incredible... Trebor  10/20/10 10:58 PM
. * Re: 74LS629 Foxhack  10/19/10 07:01 PM
. * Re: 74LS629 tamalmalamarrado  10/19/10 06:20 PM
. * Re: 74LS629 Derrick Renaud  10/19/10 07:45 PM
. * Re: 74LS629 tamalmalamarrado  10/20/10 12:16 AM
. * Re: 74LS629 Naoki  10/19/10 10:44 AM
. * Love it Sune  10/19/10 05:23 AM
. * Re: Love it redk9258  10/19/10 05:26 AM
. * Beautiful work! horseshoecrabs  10/19/10 07:04 AM
. * Re: 74LS629 gregf  10/19/10 05:12 AM
. * Re: 74LS629 Derrick Renaud  10/19/10 02:23 PM
. * Re: 74LS629 gregf  10/20/10 10:32 PM
. * Re: 74LS629 Derrick Renaud  10/21/10 02:16 PM
. * Re: 74LS629 Antny  10/19/10 08:38 PM
. * Re: 74LS629 Derrick Renaud  10/19/10 10:01 PM
. * Re: 74LS629 horseshoecrabs  10/20/10 12:02 AM
. * Re: 74LS629 Derrick Renaud  10/20/10 04:06 AM
. * Re: 74LS629 horseshoecrabs  10/20/10 03:04 PM
. * Re: 74LS629 "The Manuel"  10/19/10 03:15 PM
. * Re: 74LS629 Derrick Renaud  10/19/10 05:03 PM
. * Re: 74LS629 "The Manuel"  10/19/10 05:31 PM
. * Re: 74LS629 CrapBoardSoftware  10/19/10 09:38 PM
. * Re: 74LS629 "The Manuel"  10/19/10 09:58 PM

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