Autopilot

Autopilot takes a design from a description to a built chip in five steps: Describe, Spec, RTL + test, Build the chip and Result. Nelix Agent does the writing, the lab's real tools check every step, and you make the decisions.

Open it from Autopilot in the left sidebar. If a run of yours is still going, or finished in the last half hour, the page opens on it. New run starts a fresh one, and the Runs menu lists your earlier runs.

Start a run#

1. What should it do? Describe the block in plain words: its ports, what happens on each clock edge, and what reset does. You can also start from one of the examples.
2. Process: the process (PDK) the chip is built on. ASAP7 is a teaching process: no sign-off DRC or LVS, and it is never manufactured.
3. Clock period (ns): the time for one clock cycle, for example 20 ns = 50 MHz. Autopilot never changes it on its own.
4. Mode:
   • Engineer runs straight through and stops only for your approval and decisions.
   • Learn pauses before each step (spec, RTL + test, build) with a short explanation and a goal to try yourself first. Press Continue to see what Autopilot does and compare.
5. Press Write the spec.

What happens next#

• Spec. Autopilot writes a specification and lists any open questions. Answer them or keep the proposed answers, then press Approve spec. Nothing is written before you approve.
• RTL + test. Autopilot writes the design and a self-checking test. Real tools check every attempt (lint, simulation and Yosys), with up to 4 attempts.
• Build the chip. The build runs in the lab's normal queue, in a new draft project of its own. Your clock and pipeline are never changed without you. When a build's only problem is antenna violations, Autopilot may try up to 2 more builds with repair settings and measures each one.
• The die size. Before the build, Autopilot counts your design's real gates with a quick synthesis and sizes the die from that: the lab's starter size for small designs, bigger (up to twice the side) for bigger ones. The build settings line says so, for example die 600 x 600 um, sized from the design's 6,794 synthesized gates. If placement still stops because the cells do not fit, Autopilot rebuilds once with a die sized from that build's measured fill (at most 2,000 µm a side), shown as Attempt 2. It never changes your clock or your design to make it fit.
• Result. The measured results of the build: the checks, timing and size, as in Build results. If the build failed, the result says why in measured words, read from the build's own reports (for example that the cells did not fit the die at the set density), and the same reason appears in the timeline.

On the page while a run goes#

• The step row at the top shows the current step bigger, in colour, with a spinning ring while it runs; on a phone the steps stack vertically. Above it a small line says Live updates, Reconnecting or Updates stopped: the page keeps asking the lab for news, and if that fails five times in a row it stops and offers Try again (your run keeps going on the server either way).
• During the chip build you see Phase N of 7, which phase is running and what it does, the time elapsed and an estimate of the time remaining. The estimate is the usual time of earlier finished builds on the same process; with fewer than three such builds there is no estimate.
• The result tiles are grouped: Timing, Area (cell area and die size), Power, Misc (antenna) and Verification (DRC, LVS, tests).
• The timeline on the right has a search box, filters by step, a grouped view and Show more for long runs.

Keep the design#

Nothing is kept until you press Keep this design. You choose a name, and the files go into a new project. An existing project is never written to, so your own work is never overwritten.

The new project's Overview says Created from verified Autopilot draft …, with links to the draft's test run and chip report. Those results are marked inherited, not current: they belong to the draft. The stages in your new project show Not run until you run them, and then they are your project's own results.

If an Autopilot chip build fails, the result card says why, from the build's own log (for example the cells do not fit on the chip at this placement density), and what to try.

Limits#

• Each run may use at most 30 AI requests, and each one counts in your plan's Nelix Agent allowance. When the allowance is used up, the run stops and tells you why; you can retry once it renews.
• New Autopilot runs a month: 5 on Student and 15 for students in a licensed class. Other plans have no monthly limit. The count starts again on the 1st of the month (UTC). Runs you already started stay open. See Plans and allowances.
• If Nelix Agent is not available, Autopilot says so and does not start. It never fakes a step.

Autopilot and classes#

Autopilot always makes a new project of its own. It never touches graded class work. A student whose class is set to No AI assistance, Evidence or Diagnosis cannot start a new run while one of that class's assignments is open (the page says so and names the class); runs started earlier stay readable. Classes at Proposed repair are not limited.