13/analog-quil-examples

[cbosborn]

Add readout cavity scan example measurement in examples.md. Resolves #10.

[cbosborn]

@stylewarning @ecpeterson There are some TODOs in this PR and some open questions, hoping to start a discussion.

[ecpeterson]

This is a good question. Is capture_delay something that is also calibrated, or is it a fixed value that's baked into the hardware? If the latter, my uneducated instinct is to wrap it into the CAPTURE instruction, since it's sorta part of that fixed process. If the former, a separate DELAY is probably the right thing to do, but where you get that value from, I don't know. Perhaps that's some other sort of DEFCAL waiting to be written.

[cbosborn]

Also calibrated.

[caryan]

Capture delay should go away unless you specifically want to mess with it: it's baked into the channel delays in the rack now.

[stylewarning]

what's left on this?

[cbosborn]

@stylewarning I addressed @caryan's DELAY removal request, and I believe he has one more question he'll post shortly. I'd also like to better understand how $-prepended variables work (e.g. $qubit) before I say this is ready. I'll remove the wip when it is.

[cbosborn]

@stylewarning this PR is now ready.

[ecpeterson]

Unclear how true-to-life / useful capture_delay.quil will really end up being, but as an example of something that flexes the spec, I think it's good.