Advertisement
Digital Audio Transmitter
DAX Programming Model
The second sub-frame transmission (Channel B) starts with the preamble generator
generating the Channel B preamble (Y-preamble). At the same time, Channel B audio
and non-audio data is transferred to the XADSR shift-register from the XADBUF and
XNADBUF registers. The generated Y-preamble is output immediately after the
Channel A parity and is followed by the audio and non-audio data in the XADSR,
which is in turn followed by the calculated parity for Channel B. This completes a
frame transmission. When the Channel B parity is sent, the audio data for the next
frame, stored in the XADRA/XADRB and the non-audio data bits from the XCTR,
are uploaded.
8.4
DAX PROGRAMMING MODEL
The programmer-accessible DAX registers are shown in Figure 8-2 on page 8-7. The
registers are described in the following subsections. The Interrupt Vector table for the
DAX is shown in Table 8-1 . The internal interrupt priority is shown in Table 8-2 .
Condition
XADE & XAUR
XADE & XBLK
XADE
Priority
highest
lowest
8.5
DAX INTERNAL ARCHITECTURE
Hardware components shown in Figure 8-1 on page 8-4 are described in the
following sub-sections. The DAX programming model is illustrated in Figure 8-2 .
8-6
Freescale Semiconductor, Inc.
Table 8-1 DAX Interrupt Vectors
Address
P:$0050
DAX Transmit Underrun Error
P:$0052
DAX Block Transferred
P:$0056
DAX Transmit Register Empty
Table 8-2 DAX Interrupt Priority
Interrupt
DAX Transmit Underrun Error
DAX Block Transferred
DAX Transmit Register Empty
DSP56011 User's Manual
For More Information On This Product,
Go to: www.freescale.com
Description
MOTOROLA
Advertisement
