Datasheet

Push Buttons and Switches
2-18 ADSP-21489 EZ-Board Evaluation System Manual
Headphone Enable Switch (SW23)
The headphone enable switch (SW23) connects the AD1939’s OUT3 circuit
to the 3.5 mm headphone connector (J8). By default, the headphone
enable switch is disabled. To use the headphones, set SW23 to all ON. For
more information, see “Headphone Out Connector (J8)” on page 2-27.
Audio Loopback Switches (SW24–25)
The audio loopback switches (SW24 and SW25) are used for testing only.
The switches loop back any analog signal generated from the AD1939’s
digital-to-analog converter (DAC) circuit to analog-to-digital converter
(ADC) circuit.
Table 2-17. Multiple-Processor Configuration
Switch Position Main EZ-Board
Attached to Emulator
EZ-Board(s)
Not Attached to Emulator
SW19.1 ON OFF
SW19.2 ON ON
SW19.3 ON OFF
SW19.4 ON ON
SW19.5 ON OFF
SW19.6 ON ON
SW19.7 ON OFF
SW19.8 ON ON
SW20.1 ON OFF
SW20.2 OFF OFF
SW21.1 OFF OFF
SW21.2 ON ON
SW22.1 OFF ON
SW22.2 ON OFF