alc850 Realtek Semiconductor Corporation, alc850 Datasheet - Page 18

• Manufacturer Part Number: alc850
• Description: Eight Channel Ac?97 2.3 Audio Codec
• Manufacturer: Realtek Semiconductor Corporation

7.1.3.
Default: 8000H
These registers control the volume level of Mono-Out. Each step on the left and right channels
corresponds to a 1.5dB increase/decrease in volume.
7.1.4.
Default: 0000H
This register controls the input volume for the PC beep signal. Each step in bits 4:1 corresponds to a 3dB
increase/decrease in volume. Sixteen levels of volume are available, from 0000 to 1111.
The purpose of this register is to allow the PC Beep signals to pass through the ALC850, eliminating the need
for an external system speaker/buzzer. The PC BEEP pin is directly routed (internally hardwired) to the Front-
Out. If the PC speaker/buzzer is eliminated it is recommended to connect the external speakers at all times so
that the POST codes can be heard during reset.
Eight Channel AC’97 2.3 Audio Codec
MR/ML:
For PB
14:13
14:13
12:5
For
4:0
4:1
Bit
Bit
15
15
0
MX06 Mono-Out Volume
MX0A PC BEEP Volume
Type
Type
R/W
R/W
R/W
R/W
R/W
0Fh
00h
00h
1Fh
-
0dB attenuation
45dB attenuation
Function
Mute Control
0: Normal
1: Mute (-∞dB)
Reserved
Internal PCBEEP Frequency, F[7:0]
The internal PCBEEP frequency is the result of dividing the 48kHz clock by 4 times the number
specified in F[7:0].
The lowest tone is 48kHz/(255*4)=47Hz.
The highest tone is 48kHz/(1*4)=12kHz.
A value of 00h in F[7:0] disables internal PCBEEP generator and allows external PCBEEP input
PC Beep Volume (PBV[3:0]) in 3dB steps
Reserved
Reserved
Mono Master Volume (MM[4:0]) in 1.5dB steps
0dB attenuation
46.5dB attenuation
Function
Mute Control
0: Normal
1: Mute (-∞ dB)
Table 8. MX06 Mono-Out Volume
Table 9. MX0A PC BEEP Volume
10
Track ID: JATR-1076-21 Rev. 1.4
Datasheet
ALC850