WM8778-EV1M
w
Rev 1.1, February 2004
39
APPENDIX
DAC AND ADC ALTERNATIVE AUDIO INTERFACE CONFIGURATION
The DAC and ADC have separate left/right clocks, bit clocks, master clocks and data I/O’s.
The audio interface for each may be configured independently to operate as master or slave.
In slave mode ADCLRC, DACLRC, ADCBCLK and DACBCLK are all inputs. In master mode
ADCLRC, DACLRC, ADCBCLK and DACBCLK are outputs.
Previous configuration details (ADC, DAC and Line setup) have configured the WM8778 for
slave mode. Also the clocks for the audio interface have been generated from the SPDIF
crystal and for operation of the ADC common MCLK (short J9), LRC (short J16) and BCLK
(short J15) clocks were used. The following information details the configuration of the DAC
and ADC for master mode and also the configuration for independent DAC and ADC audio
interface.
MASTER/SLAVE MODE
The WM8778-EV1B has the ability to configure the WM8778 for independent DAC and ADC
in either master or slave mode. This means that there are four configurable options, the
following tables detail the recommended jumper settings to configure the audio interfaces for
the specified operation.
1. DAC and ADC = Slave
. This configuration has been detailed during the software operation
explanation.
2. DAC and ADC = Master
. The following switch and jumper settings should be made.
LINKS AND
JUMPERS
LINK / JUMPER /
SWITCH POSITION
DESCRIPTION
H1
Fit Jumpers (1,2) (5,6)
(9,10) (13,14)
DAC clocks and data
H2
Fit jumpers (1,2) (5,6)
(9,10)
ADC Clocks and data
J8
SHORT
DAC Master Mode (Level Shift Direction)
J9 (BCLK)
OPEN
Separate BCLK
J11 (LRC)
OPEN
Separate LRCLK
J12
SHORT
ADC Master Mode (Level Shift Direction)
J14 (MCLK)
SHORT
Link MCLK (DAC MCLK to ADC)
SW1
1 2 3 4 5 6 DATA FORMAT
0 0 0 1 0 0 I
2
S Compatible
Summary of Contents for WM8778-EV1B
Page 1: ...WM8778 EV1B Evaluation Board User Handbook Rev 1 1...
Page 25: ...WM8778 EV1M w Rev 1 1 February 2004 25 SCHEMATIC LAYOUT Figure 13 Functional Diagram...
Page 26: ...WM8778 EV1M w Rev 1 1 February 2004 26 Figure 14 Digital Input...
Page 27: ...WM8778 EV1M w Rev 1 1 February 2004 27 Figure 15 Software Control...
Page 28: ...WM8778 EV1M w Rev 1 1 February 2004 28 Figure 16 Level Shift...
Page 29: ...WM8778 EV1M w Rev 1 1 February 2004 29 Figure 17 Analogue Input and Output Mute...
Page 30: ...WM8778 EV1M w Rev 1 1 February 2004 30 Figure 18 WM8778...
Page 31: ...WM8778 EV1M w Rev 1 1 February 2004 31 Figure 19 Analogue Output...
Page 32: ...WM8778 EV1M w Rev 1 1 February 2004 32 Figure 20 Power...
Page 33: ...WM8778 EV1M w Rev 1 1 February 2004 33 WM8778 EV1B PCB LAYOUT Figure 21 Top Layer Silkscreen...
Page 34: ...WM8778 EV1M w Rev 1 1 February 2004 34 Figure 22 Top Layer...
Page 35: ...WM8778 EV1M w Rev 1 1 February 2004 35 Figure 23 Bottom Layer...
Page 36: ...WM8778 EV1M w Rev 1 1 February 2004 36 Figure 24 Bottom Layer Silkscreen...
