STN-29

About setting of CD-DA volume

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Contents

■ Overview

Decrease the CD-DA level by 6 dB so that the CD-DA volume setting in the SEGA SATURN application is not significantly different from the music CD playback volume on the multiplayer screen.

■ Correspondence method

The specific setting method is described below.

1. When setting directly to the hardware
2. When using SATURN Sound Driver
3. When using the sound I / F library

■ Supplement

When you want to actively change the CD-DA level, such as when you want to produce a special effect, use the music CD level in multiplayer as a reference and adjust the balance so that there is no significant difference in volume.

■ 1. When setting directly to the hardware

For operation, change the EFSDL [2: 0] of the slot-specific control register from 111b (-0 dB) to 110b (-6 dB). Regarding CD-DA, the slot numbers are 16 and 17, respectively, on the left and right.

Left channel : Slot number 16: Write FDH at address 100200H + 17H.
The contents of FDH are EFSDL [2: 0] = 110b (transmission level) EFPAN [4: 0] = 11111b (localization data)

Right channel : Slot number 17: Write CFH at address 100220H + 17H.
The contents of CFH are EFSDL [2: 0] = 110b (transmission level) EFPAN [4: 0] = 01111b (localization data)

The addresses from the main CPU are on the left and right respectively.

Left channel = 25B00200H + 16H

Right channel = 25B00200H + 16H

It will be.

caution:

Be sure to access the word from the main CPU.

reference:

"HARDWARE MANUAL / SCSP User's Manual" ■ 4.1 Register map

■ 2. When setting using "SATURN Sound Driver"

Use the sound control command CD-DA Level (command number 80H). Change the data from E0H (-0dB) to C0H (-6dB).
Specifically, write the following data in Command Block 1 (+ 00H) of Host interface work (700H).

data	80H	00H	C0H	C0H
meaning	COM	dummy	Left volume	Right volume

reference:

"Sound Driver Programmer's Guide"
3. Sound control command / ● 80H CD-DA LEVEL

■ 3. When setting using the sound I / F library

Use the Function CD-DA Level setting.
Change the setting value from 0xE0 (-0dB) to 0xC0 (-6dB) on both the left and right sides.

Form:
SND_SetCdLev (0xC0,0xC0)

reference:

"Programmer's Guide / Sound I / F Library User's Manual"
CD-DA Level Setting / SND_SetCdDaLev