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rollback to earlier today final one

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arcadez2003 2024-08-17 20:57:33 +01:00 committed by GitHub
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1 changed files with 4 additions and 36 deletions
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src/drivers/polepos.c
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@ -774,54 +774,22 @@ static struct namco_interface namco_interface =
{
24576000/512, /* sample rate */
8, /* number of voices */
80, /* playback volume */
100, /* playback volume */
REGION_SOUND1, /* memory region */
1 /* stereo */
};
/* The 52xx output is 4Vpp. After filtering it is 2Vpp.
* The output of the 54xx is 4Vpp. After filtering it is clamped to +1.5/-2.
* So we need to make the 52xx volume 50% of the 54xx volume.
* 52xx and 54xx ouputs are mixed together to create an output called GAINx.
* This has a total resistance to the final op-amp of 13605 when the unemulated 4066
* panning circuit is at full volume. The engine sound has a resistance of 17492.
* These values include 250 ohms of the 4066 when needed.
* This all means that the engine sound is 77% of the 54xx.
*
* Jan 13/05 D.R. - not sure about the following info.
* The Sound Buffers and Multiplexer circuit on sheet 7B is not emulated.
* Basically it is a quadraphonic 16 level mixer with a 4-bit DAC (R81-85).
* It mixes/pans the combined 52xx & 54xx output.
* The 4 speaker sit down game uses the full quad output.
* The 2 speaker stand up game combine RF-RR and LF-LR through the speakers.
*
* I set the base 54xx level at 80 and the other sounds realtive to that,
* to allow headroom when more the one effect is played.
*/
static struct namco_52xx_interface namco_52xx_interface =
{
24576000/16, /* 1.536 MHz */
80, /* volume */
REGION_SOUND3, /* memory region */
0, /* Use internal Playback frequency */
100, /* High pass filter fc */
0.3, /* High pass filter Q */
1200, /* Low pass filter fc */
0.8, /* Low pass filter Q */
.5 /* Combined gain of both filters */
25, /* volume */
REGION_SOUND3 /* memory region */
};
static struct namco_54xx_interface namco_54xx_interface =
{
24576000/16, /* 1.536 MHz */
80, /* volume */
{ RES_K(22), RES_K(15), RES_K(22) }, /* R121, R133, R139 */
{ RES_K(12), RES_K(15), RES_K(22) }, /* R125, R137, R143 */
{ RES_K(120), RES_K(120), RES_K(180) }, /* R122, R134, R140 */
{ 470, 470, 470 }, /* R123, R135, R141 */
{ CAP_U(.0022), CAP_U(.022), CAP_U(.047) }, /* C27, C29, C33 */
{ CAP_U(.0022), CAP_U(.022), CAP_U(.047) }, /* C28, C30, C34 */
{ 100, 100, 100 } /* volume of the three outputs */
};
static struct CustomSound_interface custom_interface =