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6.4
Program Description
6.5
Indicators and Main Screen Controls
Kit Operation
After the TLV320AIC32EVM-PDK software installation (described in
Section 6.2
) is complete, evaluation
and development with the TLV320AIC32 can begin.
Figure 2
illustrates the indicators and controls near the top of the software screen display, and a large
tabbed interface below. This section discusses the controls above this tabbed section.
At the top left of the screen is an Interface indicator. The TLV320AIC32 has an I
2
C interface. The
indicator is lit after the program begins.
To the right of the Interface indicator is a group box called Firmware. This box indicates where the
firmware being used is operating from—in this release, the firmware is on the USB-MODEVM, so you
should see USB-MODEVM in the box labeled Located On:. The version of the firmware appears in the
Version box below this.
To the right, the next group box contains controls for resetting the TLV320AIC32. A software reset can be
done by writing to a register in the TLV320AIC32; the writing is accomplished by pushing the button
labeled Software Reset. The TLV320AIC32 also may be reset by toggling a pin on the TLV320AIC32,
which is done by pushing the Hardware Reset button.
CAUTION
In order to perform a hardware reset, the RESET jumper (JMP9) must be
installed and SW2-7 on the USB-MODEVM must be turned OFF. Failure to
do either of these steps results in not generating a hardware reset or
causing unstable operation of the EVM, which may require cycling power
to the USB-MODEVM.
The ADC Overflow and DAC Overflow indicators light when the overflow flags are set in the
TLV320AIC32. These indicators, as well as the other indicators on this panel, update only when the
software's front panel is inactive, once every 20ms. Below these indicators are other indicators that show
when the AGC noise threshold is exceeded. To the far right on this screen, the short-circuit indicators
show when a short-circuit condition is detected, if this feature has been enabled. Below the short-circuit
indicators is a bar graph that shows the amount of gain which has been applied by the AGC, and
indicators that light when the AGC is saturated.
6.5.1
Audio Analyzer
Near the left side of the screen is a button labeled Audio Analyzer; this button can be set to ON or OFF.
Pressing the button to turn it ON opens another window (see
Figure 3
). This feature provides the ability to
generate signals to be sent to the TLV320AIC32 DACs, as well as viewing and analyzing signals read by
the TLV320AIC32 ADCs. This ability to view and process the real-time streaming USB audio is a
demanding task. Use of the Audio Analyzer feature requires a PC with at least 512MB of memory and
reasonable processor speed (> 1GHz); computers with inadequate resources could still use the Audio
Analyzer to generate signals for the DACs, but will be unable to process signals from the ADCs because
the FFT, distortion analysis, and signal-to-noise ratio analysis will not be able to keep up with the data
processing requirements.
The Audio Analyzer features two tabs. The front tab, shown in
Figure 3
and titled Generator, creates
digital waveforms to send to the DACs. When first started, the function will be set to SNR (Output Zeros)
which feeds only zero codes to the DAC. This function is commonly performed to test for the noise floor of
the DAC.
The second function available is THD (-1dB sinewave). This function sends a sinewave at a coherent
frequency to the 44.1kHz sample rate to the DACs; this function is commonly used for testing THD+N.
These first two functions do not require any further settings; therefore, the frequency and amplitude knobs
below the function selector are not used. Selecting a function of Function Generator allows the choice of
waveform shape by using the pull-down menu next to the function selector, and the frequency and
amplitude of that signal can be varied using the knobs below.
SBAU113 – November 2005
TLV320AIC32EVM and TLV320AIC32EVM-PDK User's Guide
11
