DE2-115 Datasheet, PDF (85/116 Pages) Altera Corporation – The DE2-115 package contains all components needed to use the DE2-115 board in conjunction with a computer that runs the Microsoft Windows OS.

Note: execute DE2_115_NIOS_DEVICE_LED\demo_batch\nios_device_led.bat will
download .sof and .elf files.
Figure 6-6 illustrates the setup for this demonstration.
Figure 6-6 Setup for the USB device demonstration
6.5 A Karaoke Machine
This demonstration uses the microphone-in, line-in, and line-out ports on the DE2-115 board to
create a Karaoke Machine application. The Wolfson WM8731 audio CODEC is configured in the
master mode, with which the audio CODEC generates AD/DA serial bit clock (BCK) and the
left/right channel clock (LRCK) automatically. As indicated in Figure 6-7, the I2C interface is used
to configure the Audio CODEC. The sample rate and gain of the CODEC are set in this manner, and
the data input from the line-in port is then mixed with the microphone-in port and the result is sent
to the line-out port.
For this demonstration the sample rate is set to 48kHz. Pressing the pushbutton KEY0 reconfigures
the gain of the audio CODEC via I2C bus, cycling within ten predefined gain values (volume levels)
provided by the device.
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