Yamaha YMF795, Руководство пользователя

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YMF795
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$35h Speaker volume control
$36h FM volume control
$37h Earphone output volume control
Default: 0000h
Index b15 b14 b13 b12 b11 b10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
$35-7h 0 0 0 0 0 0 0 0 0 0 0 V 4 V 3 V 2 V 1 V 0
These bits are used to set the volume of each source. The volume setting consists of 31 steps and MUTE state, and can
be set in 1dB steps. As the MUTE is selected in the default state, cancel and use the MUTE state before sound
generation. And, be sure to power down the volume after muting it.
Relation between register setting value and volume.
V[4:0] Volume(dB) V[4:0] Volume(dB) V[4:0] Volume(dB) V[4:0] Volume(dB)
00h MUTE 08h -23 10h -15 18h -7
01h -30 09h -22 11h -14 19h -6
02h -29 0Ah -21 12h -13 1Ah -5
03h -28 0Bh -20 13h -12 1Bh -4
04h -27 0Ch -19 14h -11 1Ch -3
05h -26 0Dh -18 15h -10 1Dh -2
06h -25 0Eh -17 16h - 9 1Eh -1
07h -24 0Fh -16 17h - 8 1Fh 0
$38h Power Management control
Default: 001Eh
Index b15 b14 b13 b12 b11 B10 b9 b8 b7 b6 b5 b4 b3 b2 b1 b0
$38h 0 0 0 0 0 0 0 0 0 0 0 AP4 AP3 AP2 AP1 DP
These bits are used to control the power-down. 1 digital line and 4 analog lines can be independently controlled. (For
details, refer to “ ■ Power-down control division diagram”.)
Setting all bits to “1” will minimize the power of the entire LSI.
DP : Setting of “1” can power down the entire digital section.
AP1 : Setting of “1” can power down the VREF circuit in the analog section.
AP2 : Setting of “1” can power down the FM volume, speaker volume, equalizer circuit, and the non-inverted
amplifier side of speaker output section.
AP3 : Setting of “1” can power down the inverted amplifier side of the speaker output section.
AP4 : Setting of “1” can power down the DAC and earphone output volume.
After initialization, the analog section (AP1 to AP4) is in the power-down state.