Texas Instruments TLV320AIC23 manual I2C Adjust, Clock Select Button, Frequency Display Areas

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I2C Adjust

4.4.18Clock Select Button

Clicking the Clock Select button opens a panel that allows selection of master clock speed and ADC and DAC sampling rates (see Section 4.6.11). (Do clock selections correspond to sampling rate register bits?)

4.4.19 Frequency Display Areas

In the lower right corner of the main panel are two frequency displays. The one on the left shows the master clock frequency MCLK in megaHertz; the one on the right shows the DAC sampling frequency in kiloHertz.

4.5 I2C Adjust

The I2C commands are generated on the parallel port using a method referred to as bit-banging. Because Windowsdoes not have readily accessible timers down into the microseconds, the I2C clocks are done using C++ for-loops to create the delay. The number of executions of the for-loop is calibrated initially when the program is started. This initial calibration sets SCL to 100 kHz. The looping variable in the for-loop can be changed using the SCL period A and

"buttons, which only become active after clicking the Fine Adjust button. To see the result of changing this variable, requires capturing the SCL output on a storage oscilloscope. The program recalibrates SCL to 100 kHz if the RECALIBRATE button is pressed.

Figure 4–3. I2C Adjust

Software4-7

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Contents User’s Guide Important Notice EVM Important Notice EVM Warnings and Restrictions Related Documentation From Texas Instruments How to Use This ManualRead This First About This ManualTrademarks Contents Figures Introduction Page Quick Start-Up Page Topic Theory of OperationTLV320AIC23 EVM2 Parts Location Diagram TLV320AIC23 EVM2 Top View Photographs of EVMTLV320AIC23 EVM2 Bottom View Parallel Port Interface Board Top View Jumper Settings TLV320AIC23 EVM2 PowerAnalog Connections Digital Loopback TLV320AIC23 EVM2 FeaturesDigital I/O Master ClockPage Software DASCCTAIC23 Installation AIC23/DAC23 EVM2 Connection Diagram About Button DASCCTAIC23 Start-Up DASCCTAIC23 Overview Main PanelMessage Area Line Input VolumeHeadPhone Volume Reset ButtonDataLog On Check Box 9 I2C Adjust ButtonNormal Mode and USB Mode Radio Buttons 10 I2C Bypass Check BoxI2C Adjust Clock Select ButtonFrequency Display Areas View Registers Preset ModesMode Files Audio Analog Register 6 OK, Apply, and Cancel ButtonsVol Line Input Register Vol HeadPhone RegisterAudio Digital Register Analog ControlAudio Format Register Power Down RegisterSampling Rate Register Format ControlInterface Activate Register Clock SetupDevice can be undetermined I2C Error MessagesPage Kit Contents TLV320AIC23 EVM2 Kit Contents Description Qty Part Number Mfr Ref. Des Bill of MaterialsERJ-8RQJ3R3V Circuit Card and Schematic Thu Nov 29 104853 Thu Nov 29 104627 Thu Nov 29 104713 Page
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