EMP202 Datasheet, PDF (9/28 Pages) List of Unclassifed Manufacturers – Single-Chip Dual-Channel AC’97 Audio Codec for PC Audio Systems

Single-Chip Dual-Channel AC’97 Audio Codec
EMP202
EMPIA Technology
5.1.3.MX04 Headphone Volume
Default: 8000H
These registers control the overall volume level of the output functions. Each step on the left and right
channels corresponds to 1.5dB in increase/decrease in volume.
Bit
Type
Function
15
R/W
Mute Control:
0: Normal
1: Mute (- ‡dB)
14:13
-
Reserved
12:8
R/W
Headphone Left Volume: (HPL[4:0]) in 1.5 dB steps
7:5
-
Reserved
4:0
R/W
Headphone Right Volume: (HPR[4:0]) in 1.5 dB steps
1) For HPL/HPR:
00h 0 dB attenuation
1Fh 46.5 dB attenuation
2 HPL/HPR are 5-bit R/W variables. The 6th bit implementation is optional. For this reason, when the 6th bit is
written with a 1, it is the equivalent to writing the low 5-bits with 1. For example, writing 1xxxxx will read
back 01111.
5.1.4. MX06 MONO_OUT Volume
Default: 8000H
Mono output is the same data sent on all output channels. Each step in bits 4:0 corresponds to 1.5dB
in increase/decrease in volume, allowing 32 levels of volume from 00000 to 11111.
Bit
Type
Function
15
R/W
Mute Control:
0: Normal
1: Mute (- ‡dB)
14:5
-
Reserved
4:0
R/W
Mono Master Volume: (MM[4:0]) in 1.5 dB steps
1) For MM: 00h 0 dB attenuation
1Fh 46.5 dB attenuation
2) Implements 5-bit volume control only. Writing 1xxxxx will be interpreted as x11111 and will respond, when read,
with x11111.
5.1.5.MX0A PC BEEP Volume
Default: 8000H
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. 16 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 EMP202, eliminating
the need for an external system speaker/buzzer. The PC BEEP pin is directly routed (internally
hardwired) to the LINE-OUTL & R pins. If the PC speaker/buzzer is eliminated, it is recommended to
connect the external speakers at all times so the POST codes can be heard during reset.
Bit
15
14:5
4:1
0
1) For PB:
Type
R/W
-
R/W
-
00h
0Fh
Function
Mute Control:
0: Normal
1: Mute (- ‡dB)
Reserved
PC Beep Volume: (PB[3:0]) in 3 dB steps
Reserved
0 dB attenuation
45 dB attenuation
7/15/2002
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