ad1848 Analog Devices, Inc., ad1848 Datasheet - Page 17

• Manufacturer Part Number: ad1848
• Description: Parallel-port 16-bit Soundport Stereo Codec
• Manufacturer: Analog Devices, Inc.

REV. 0
Clock and Data Format Register (IXA3:0 = 8)
The contents of the Clock and Data Format Register cannot be changed except when the AD1848K is in Mode Change Enable (MCE) state.
Write attempts to this register when the AD1848K is not in the MCE state will not be successful.
CSS
CFS2:0
Note that the AD1848K’s internal oscillators can be overdriven by external clock sources at the crystal input pins. If an external
clock source is applied, it will be divided down by the selected Divide Factor. It need not be at the recommended crystal frequencies.
S/M
L/C
FMT
res
This register’s initial state after reset is “x000 0000.”
IXA3:0
8
Clock Source Select. This bit selects the crystal clock source which will be used for the audio sample rate.
0
1
Clock Frequency Divide Select. These bits select the audio sample rate frequency. The actual audio sample rate depends
on which crystal clock source is selected and the frequency of that source.
Stereo/Mono Select. This bit determines how the audio data streams are formatted. Selecting stereo will result with alter-
nating samples representing left and right audio channels. Mono playback plays the same audio sample on both chan-
nels. Mono capture only captures data from the left audio channel.
0
1
Linear/Companded Select. This bit selects between a linear digital representation of the audio signal or a nonlinear,
companded format for all input and output data. The type of linear PCM or the type of companded format is defined by
the FMT bits.
0
1
Format Select. This bit defines the format for all digital audio input and outputs based on the state of the L/C bit.
Reserved for future expansion. Always write a zero to this bit.
XTAL1 (24.576 MHz)
XTAL2 (16.9344 MHz)
Mono
Stereo
Linear PCM
Companded
Data 7
res
CFS
0
1
2
3
4
5
6
7
0
1
Data 6
FMT
Linear PCM (L/C = 0)
8-bit Unsigned PCM
16-bit Twos-Complement PCM
Divide
Factor
3072
1536
896
768
448
384
512
2560
Data 5
L/C
XTAL1
24.576 MHz
8.0 kHz
16.0 kHz
27.42857 kHz
32.0 kHz
Not Supported
Not Supported
48.0 kHz
9.6 kHz
Data 4
S/M
–17–
XTAL2
5.5125 kHz
11.025 kHz
18.9 kHz
22.05 kHz
37.8 kHz
44.1 kHz
6.615 kHz
16.9344 MHz
33.075 kHz
Data 3
CFS2
Companded (L/C = 1)
8-bit -law Companded
8-bit A-law Companded
Data 2
CFS1
Data 1
CFS0
AD1848K
Data 0
CSS