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Using the DAC8881EVM with DXP
The DXP software defaults to output a 1 kHz sine wave from the DAC, other waveform options include
Square, Saw tooth, Triangle and DC output options as described in the DXP Users Guide. GPIO options
are available on the DAC8881EVM which will activate either the RESET or Power down functions of the
DAC8881. These are shown below in the right side of the screen labeled GPIO-controlled DAC Functions
and described in
Table 8 .
Table 8. DXP GPIO Controlled DAC Functions
Function Detailed Description
Reset Pressing the reset button will cause the button to turn ACTIVE and places logic low on pin 17 of the DAC8881. To
use this function, please ensure no jumpers are placed on J1 pins 9-10. When the RST pin is low, the device is in
hardware reset mode, and the input register and DAC latch are set to the value defined by the RSTSEL pin (refer
to the DAC8881EVM Schematic; J1, pins 3-4). Pressing reset a second time returns the RST function to its inactive
state. The device is in normal operating mode, and the input register and DAC output will maintain the reset value
until new data are written.
Power Down Pressing the Power-down button will cause the button to turn ACTIVE and places logic high on pin 18 of the
DAC8881. To use this function, please ensure no jumpers are placed on J1 pins 11–12.
Figure 13. DAC8881 – Frequency/Amplitude and GPIO Control Options
19 SLAU257A – September 2008 – Revised November 2009 DAC8881 Evaluation Module
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