Tools
Web Search and Exa Search
Two ways to pull outside material into a run, and which one suits which question.
Two of the four retrieval switches reach outside SiliCode. They answer different kinds of question, and turning both on at once is rarely useful.
Web Search
Web Search allows the RTL generator to retrieve up-to-date public information. It is useful when the request depends on information that may not already be available in the model's built-in knowledge, such as current vendor documentation, protocol updates, implementation notes, reference designs, errata, and other technical resources available publicly online.
It is the right switch when the answer exists on a page somewhere and you would otherwise go and look it up yourself: a register map, the timing a peripheral expects, or the exact framing of a protocol you half-remember.
Example
If you ask for an RTL interface to a recently released FPGA device, Web Search can retrieve the latest documentation before generating the module.
Note
Search results are context, not gospel. Anything it finds still has to survive the testbench, and a wrong page produces a confidently wrong module. If you already know the numbers, put them in the spec instead; that is both faster and more reliable.
Exa Search
Exa Search is a more technical, meaning-based retrieval mode. Instead of primarily searching by keywords the way Web Search does, it is intended to find documents that are conceptually relevant to the engineering problem being solved.
This is particularly useful for locating datasheets, technical papers, architecture descriptions, application notes, and similar engineering material. It works at the level of the relevant passage rather than the whole page, which is what makes it the better switch for standards work such as AXI, AHB, I2C, SPI, Ethernet framing and PCIe.
Example
For a high-throughput packet scheduler, Exa Search may retrieve papers describing scheduling architectures even when they use terminology different from your prompt.
Web Search vs. Exa Search
Think of Web Search as broad live information retrieval, while Exa Search is better suited to finding technically relevant documents by meaning.
| Question | Tool |
|---|---|
| What is the reset value of register 0x1C on this chip? | Web Search |
| How is a CRC-32 usually pipelined for a 64-bit datapath? | Exa Search |
| What baud rate divisors does this dev board use? | Web Search |
| What does the AXI spec say about WLAST on a single-beat write? | Exa Search |
Cost and time
Both add a step before generation, so a turn takes longer. Search happens inside the turn and may increase how much credit it uses.
If Exa is greyed out
Exa is an optional integration. If the switch does nothing or the run reports no results, that integration is not enabled where you are running; Web Search is the fallback and needs no extra configuration.