Core concepts
Workspaces
From scratch or inside an existing project; the choice that shapes everything else.
The first choice on a new chat is what RTLBridge starts from: a blank page or your own files. It is the decision that shapes everything else about the run, so it sits above the composer rather than being buried in a settings panel.
The switch
From scratch
The default. You describe a module and get a fresh one back, along with its testbench and reports. Nothing of yours is involved beyond the words you typed and your coding style preferences.
Use it when:
- You want a self-contained block: a FIFO, a UART, an arbiter, a CRC unit.
- You are prototyping an interface and want to see a reasonable first shape for it.
- You want VHDL. Project mode is Verilog only.
- You want the Plan mode flow, with clarifying questions before any code is written.
Existing project
You upload a zip of your RTL and RTLBridge works inside it the way a new engineer would: reads the files, makes the change you asked for, runs what it can, and hands you a diff. Your files are edited in place, not rewritten from scratch.
Use it when:
- The change spans more than one file, or depends on code you already have.
- You want a bug found rather than a module written.
- You need a testbench for something that already exists.
- You want to ask questions about a codebase before changing anything.
Heads up
Project mode always runs on the agent loop and always produces Verilog. Asking for Plan mode or VHDL alongside it is rejected rather than quietly downgraded, so you are never surprised by a run that did something other than what the controls said.
The details are in Upload a project.
Can one chat do both?
No, and that is on purpose. A chat that started as a project chat stays one; every follow-up in it edits the same workspace. If you want a standalone module instead, start a new chat. The mode toggle in a project chat is replaced by a fixed Agent label so the choice cannot be made by accident.