RCVDL56DPFL/SP, RCV56DPFL/SP, and RCV336DPFL/SP Designer’s Guide
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12.1.9 Speaker Attenuation/Gain Control
Speaker Gain Control
The speaker gain may be controlled through the VOLUME bits (01h:7-6):
Speaker Attenuation (dB)
Value in 01h:7-6 (Bin)
Speaker off
00
0 dB (high volume)
01
6 dB (medium volume)
10
12 dB (low volume)
11
The speaker gain may also be altered through address 990h. This location is reset to default after a RREN and is adjustable
only when the modems are connected. The speaker volume is relative to the microphone gain of the remote audio source.
Values written to address 990h do not correspond to absolute output levels but rather to relative changes in output level. The
following table illustrates the relative gain in 2 dB steps:
Speaker Relative Gain (dB)
Value in 990 (Hex)
+10
FC00 (maximum)
+8
FA00
+6
F800
+4
F400
+2
F200
0
F000 (default)
-2
EC00
-4
EA00
-6
E700
-8
E400
-10
E200
12.1.10 Microphone Gain Control
The microphone gain is controlled through bits 3D3h:2-1:
Microphone Gain (dB)
Value in 3D3h:2-1 (Bin)
0
00
10
01
15
10
20
11
Summary of Contents for RC336DPFL
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