CS49300 Family DSP
particular mode is desired that is not presented,
please contact your sales representative as to its
availability.
9. HARDWARE CONFIGURATION
After download or soft reset, and before
kickstarting the application (please see the Audio
Manager in the Application Messaging Section of
any Application Code User’s Guide for more
information on kickstarting), the host has the
option of changing the default hardware
configuration. Hardware configuration messages
are used to physically reconfigure the hardware of
the audio decoder, as in enabling or disabling
address checking for the serial communication
port. Hardware configuration messages are also
used to initialize the data type (i.e., PCM or
10.1. Digital Audio Formats
This subsection will describe some common audio
formats that the CS493XX supports. It should be
noted that the input ports use up to 24-bit PCM
resolution and 16-bit compressed data word
lengths. The output port of the CS493XX provides
up to 24-bit PCM resolution.
10.1.1.I2S
2
Figure 43, "I S Format" on page 68 shows the I2S
2
compressed) and format (e.g., I S, left justified,
format. For I2S, data is presented most significant
bit first, one SCLK delay after the transition of
LRCLK and is valid on the rising edge of SCLK.
For the I2S format, the left subframe is presented
when LRCLK is low and the right subframe is
presented when LRCLK is high. SCLK is required
to run at a frequency of 48Fs or greater on the input
ports.
etc.) for digital data inputs, as well as the data
format and clocking options for the digital output
port.
In general, the hardware configuration can only be
changed immediately after download or after soft
reset. However, some applications provide the
capability to change the input ports without
affecting other hardware configurations after
sending a special Application Restart message
(please see the Audio Manager in any Application
Code User’s Guide to determine whether the
Application Restart message is supported). Section
11.4 at the end of this chapter will describe how to
construct a hardware configuration message.
10.1.2.Left Justified
Figure 44 shows the left justified format with a
rising edge SCCLK. Data is presented most
significant bit first on the first SCLK after an
LRCLK transition and is valid on the rising edge of
SCLK. For the left justified format, the left
subframe is presented when LRCLK is high and the
right subframe is presented when LRCLK is low.
The left justified format can also be programmed
for data to be valid on the falling edge of SCLK.
SCLK is required to run at a frequency of 48Fs or
greater on the input ports.
10. DIGITAL INPUT & OUTPUT
The CS493XX supports a wide variety of data
input and output mechanisms through various input
and output ports. Hardware availability is entirely
dependent on whether the software application
code being used supports the required mode. This
data sheet presents most of the modes available
with the CS493XX hardware. This does not mean
that all of the modes are available with any
particular piece of application code. The
application code user’s guide for the particular
code being used should be referenced to determine
if a particular mode is supported. In addition if a
10.1.3.Multichannel
Figure 45 shows the multichannel format. In this
format up to 6 channels of audio are presented on
one data line with M bits per channel. Channels 0,
2, and 4 are presented while the LRCLK is high and
channels 1, 3, 5 are presented while the LRCLK is
low. Data is valid on the rising edge of SCLK and
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