12-12
DSP56367
MOTOROLA
Digital Audio Transmitter
DAX Programming Considerations
Figure 12-5 shows how each clock is divided to generate the biphase and bit shift clocks
Figure 12-5 Clock Multiplexer Diagram
Note:
For proper operation of the DAX, the DSP core clock frequency must be at least
five times higher than the DAX bit shift clock frequency (64
×
Fs).
12.5.12
DAX STATE MACHINE
The DAX state machine generates a set of sequencing signals used in the DAX.
12.6
DAX PROGRAMMING CONSIDERATIONS
The following sections describe programming considerations for the DAX.
12.6.1
INITIATING A TRANSMIT SESSION
To initiate the DAX operation, follow this procedure:
1. Ensure that the DAX is disabled (PC1 and PC0 bits of port control register PCR are
cleared)
2. Write the non-audio data to the corresponding bits in the XNADR register
3. Write the channel A and channel B audio data in the XADR register
4. Write the transmit mode to the XCTR register
1/4
2/3
1/2
1/2
1/2
Biphase
Clock
(128
×
Fs)
Bit Shift
Clock
(64
×
Fs)
DSP Core Clock
(1024
×
Fs)
ACI Pin
{256,384,512}
×
Fs
(XCS1 or XCS0)
XCS0
1
0
XCS1
1
0
1
0
MU
X
MUX
MU
X
AA0610
Summary of Contents for DSP56367
Page 16: ...xvi MOTOROLA CONTENTS Paragraph Number Title Page Number ...
Page 22: ...xxii MOTOROLA List of Figures Figure Number Title Page Number ...
Page 26: ...xxvi MOTOROLA List of Tables Table Number Title Page Number ...
Page 148: ...4 6 DSP56367 MOTOROLA Design Considerations PLL Performance Issues ...
Page 248: ...9 30 DSP56367 MOTOROLA Serial Host Interface SHI Programming Considerations ...
Page 306: ...10 58 DSP56367 MOTOROLA Enhanced Serial Audio Interface ESAI ESAI Initialization Examples ...
Page 389: ...Bootstrap ROM Contents MOTOROLA DSP56367 A 15 end ...
Page 390: ...A 16 DSP56367 MOTOROLA Bootstrap ROM Contents ...
Page 432: ...C 8 DSP56367 MOTOROLA JTAG BSDL ...
Page 484: ...D 52 DSP56367 MOTOROLA Programmer s Reference ...
Page 490: ...E 6 DSP56367 MOTOROLA Power Consumption Benchmark ...
Page 516: ...F 26 DSP56367 MOTOROLA IBIS Model ...
Page 522: ...Index 6 MOTOROLA Index ...
Page 523: ......