Override DAC values and DDS attenuation in dashboard applet

[Shao-Wen-Chang]

ARTIQ Feature Request

Problem this request addresses

The DAC applet in ARTIQ 7 only shows the current output value of each channel, but it does not provide a means to override the outputs like the TTL applet does. The DDS applet allows one to set the output frequencies manually, but it has no control over the attenuation.

Describe the solution you'd like

For the DAC applet:

• Add an "override" button to each of the DAC channel, which when activated allows the user to set the output value of that channel, while ignoring e.g. calls of set_dac() in submitted experiments.

For the DDS applet:

• Add an "attenuation" button to each of the DDS channel for the user to set desired attenuation.
• Add an "override" button to each of the DDS channel. Ideally one would be able to override frequency and attenuation separately.