SBAU012 Datasheet, PDF (9/11 Pages) Texas Instruments – COMPLETE EVALUATION PLATFORM FOR THE PCM1604 SIX-CHANNEL AUDIO D/A CONVERTER

Although the Attenuation window is used to set the level of
the attenuation registers, the actual attenuators inside the
PCM1604 will not be updated unless the attenuation load
control, ATLD (in the Operational Control window) is set to
LOAD. While ATLD is set to OFF, the attenuation registers
are written to, but the attenuators are not updated. When
ATLD is switched from OFF to LOAD, all attenuators will
be updated simultaneously.
Operational Control Window
The Operational Control window (labeled DAC Operation)
is used to program the soft mute (MUT1-6), DAC operation
(DAC1-6), attenuation load (ATLD), attenuation rate (ATTS),
and infinite zero detect mute (IZD) functions. The mute,
DAC operation, and infinite zero mute functions are set
using check boxes, as shown in Figure 7. The labels associ-
ated with the check boxes change from ON to OFF as the
settings are toggled. The attenuation load and rate functions
utilize pull-down menus to set ATLD to Disable or Enable,
and ATTS to 2/f_S or 4/f_S.
For more information regarding these functions, please refer
to the PCM1604 Product Data Sheet.
Register Read Window
The PCM1604 serial control interface includes register read
capability. The Register Read window (or panel) allows the
user to read the value of all PCM1604 registers by pressing
a single button. The panel is shown in Figure 9. The Register
Read panel provides a means to check for proper communi-
cations between the PC printer port and the DEM-DAI1604
by allowing the user to verify register write operations.
FIGURE 8. Function Control Window.
FIGURE 7. Operational Control Window.
Function Control Window
The Function window hosts the remainder of the PCM1604
control functions. All functions are programmed using pull-
down menus, as shown in Figure 8. Functions that can be
programmed by this window include:
• SCLKO Output Enable (CLKE) and Rate (CLKD) Controls
• De-Emphasis Controls (DM12, DM34, DM56) and Sample
Rate Selection (DEM)
• Audio Data Format (I/F FORMAT)
• Digital Filter Roll-Off (ROLL-OFF)
• Output Phase (Normal or Inverted)
• Oversampling (64fs or 128fs)
These functions are described in detail in the PCM1604
Product Data Sheet.
FIGURE 9. Register Read Window.
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DEM-DAI1604