Analog Devices ADSP-21369 system manual LEDs and Push Buttons

LEDs and Push Buttons

routing unit (SRU). It is also necessary to disable the on-board audio oscillator from driving the audio codec and the processor’s input pin. For instructions on how to configure the clock, refer to “Codec Setup Switch (SW3)” on page 2-10.

The AD1835A codec can be configured as a master or as a slave, depend- ing on the DIP switch settings. In master mode, the AD1835A drives the serial port clock and frame sync signals to the processor. In slave mode, the processor must generate and drive all of the serial port clock and frame sync signals. For information on how to set the mode, refer to “Codec Setup Switch (SW3)” on page 2-10.

The AD1835A audio codec’s internal configuration registers are config- ured using the SPI port of the processor. The DPI pin 4 (DPI4 register) is used as the select for the device. For information on how to configure the multichannel codec, refer to the codec’s datasheet, which can be found at

http://www.analog.com/en/prod/0,2877,AD1835A,00.html.

The RCA connector (P10) is used to input analog audio. When using an electret microphone on this connector, configure the SW4 switch according the instructions in “Electret Microphone Select Switch (SW4)” on page 2-11. The four output channels connect to the RCA connector J5. Channel 4 of the codec connects to the headphone jack P7. For more information about the connectors see “Connectors” on page 2-20.

Example programs are included in the EZ-KIT Lite installation directory to demonstrate how to configure and use the board’s analog audio interface.

LEDs and Push Buttons

The EZ-KIT Lite has eight general-purpose user LEDs and four gen- eral-purpose push buttons.

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