Chapter overview
Bottom line: Use only three types of symptom cards without live-environment values, and the offline judgment evidence is "missing candidate item", "candidate path category change" or "driver-category clue". You do not look at the device list, copy paths or serial numbers, and you do not try the driver, reboot, or touch the bus.
- Purpose
- Complete an offline decision tree for USB/serial interfaces using three categories of de-identified symptoms.
- Prepare
- A blank three-branch worksheet with pinned sources; no USB device, logs, or execution environment required.
- Time
- About 20 minutes
- System change
- Do not access or restart a USB/serial interface; organize only de-identified offline fault classifications.
- Expected result
- Distinguish evidence of a missing device, changed path, and driver failure without claiming that an interface or hardware works.
- Stop conditions
- Do not copy the actual device path, USB serial number or host data.
- Stop if the task would require reconnecting hardware, loading a driver, restarting a service, or accessing the bus.
Scope and safety boundaries
This chapter only compiles de-identified symptom cards. Safe work is limited to offline, read-only pinned sources or placeholder classification that never accesses an execution environment. Read-only viewing in any live/running environment is approval-required, and this chapter does not provide a viewing method.
- Safe: Read the locked source and create three types of blank cards: "Missing Candidate Item", "Candidate Path Category Change" and "Driver Category Clues".
- Isolated test: Alternative projects must first have clear written approval, a non-production test environment, administrator presence, limited network exposure, and a proven stop-and-recovery plan; they are not covered in this chapter.
- Approval required: This is true for viewing or changing any running environment; approval for read-only does not equal approval for attempts or modifications.
- Never automate: Do not read or write groups, send a KNX telegram, perform ETS programming or downloads, connect a KNX interface or bus, or control physical equipment. The test bus is no exception.
Joining the repository, installing or starting also requires full isolation gates, written approval, approved immutable artifact/image digest and source-to-build attestation. Stop if any item is missing.
Core concepts
Sort the items first, then decide who takes over. The symptom card only determines the file destination, not the live-environment root cause.
Three opaque inboxes
Think of it this way: The office receives three notices without names or addresses: an expected package did not appear as a candidate, the package's path category differs from the earlier record, or a driver-category clue is present. The desk only sorts notices into trays; it does not open or trace packages or declare them ready for use.
Formal term: Anonymous symptom classification for missing candidate, path-change, and driver-category.
How this chapter uses it: A "candidate" is only an abstract item described by the source for configuration preparation; a "path change" indicates only a changed category relationship; a "driver category" indicates only documented responsibility. None of the three prove USB, serial interface, or hardware status.
The initialization source of Add-on 0.6.1 can describe the interface, USB value conversion and configuration preparation responsibilities of the required device; the upstream 0.14.72 file can describe the driver family and documented diagnostic concepts. Neither source provides a candidate, path, serial number, or result for a specific host.
Preparation and prerequisites
Draw the decision tree before looking for a device. The root node asks only, "Which symptom matches the existing de-identified description?" Mark every other branch "insufficient information."
- Missing candidate card: Just write "the expected category did not produce a candidate"; do not write the candidate content, enumeration results or occurrence position.
- Candidate path category change card: Only write "the reference type is different from the original record"; do not write the old value, new value or device relationship.
- Driver-category clue card: Record only the responsibility categories in the pinned source; list no trial order, compatible models, or loading methods.
- Unknown card: When information is mixed, from unknown sources, or when live-environment values are needed, stop classifying and leave it unknown.
Worksheets may not contain device paths, USB serial numbers, hosts, endpoints, addresses, accounts, secrets, environment names, or times that can be associated with a site. If the material you have contains these contents, do not copy them; return them to controlled privacy processes.
Steps
Each step only processes offline text. You do not need to ask the system to answer any questions.
- Confirm source boundaries. Only the initialization responsibilities and driver documented concepts described in the locked version are accepted. If there is no source, it is marked as insufficient information.
- Remove live-site details. Only retain abstract descriptions such as "missing", "different reference categories" or "driver responsibility category"; stop when the material can still identify the environment.
- Evaluate the first branch. If the description only says that the expected category was not a candidate, add a missing-candidate card; do not guess at hardware, permissions, or reasons.
- Evaluate the second branch. If the description only says that the reference category is different before and after, add a path-category-change card; do not remember any old values, new values, or enumeration methods.
- Evaluate the third branch. If the description can only correspond to the driver responsibility or failure concept in the document, put it in the driver-category clue card; do not generate trial suggestions.
- Limit conclusions. Each card says "Only document classification supported; all live-environment availability not confirmed."
- Independent review. Confirm by another reader that the branch is single, from a pinned source, has no identifying values, and has no commands, enumerations, tryouts, restarts, or bus actions.
Verification and evidence
The finished product is an anonymous offline decision tree. It is not a diagnosis and does not indicate that any device has been viewed, detected or verified.
- The root node only accepts de-identified symptom statements supported by pinned sources.
- The three branches are precisely the lack of candidate items, candidate path category changes, and driver-category clues.
- Each card has a source category, symptom category, evidence limit, unknown matter, and responsible role.
- There is no device path, USB serial number, host, endpoint, address, environment name, or time to associate.
- There are no commands, device enumeration, driver testing, hardware plugging, service restarting, or bus actions.
- USB, serial interface, driver, KNX bus, ETS, integration, group and physical control results remain unconfirmed.
Next step: Go to Chapter 21, arrange offline source review, approval boundaries and evidence notes into a controlled maintenance rhythm.
Troubleshooting
- The narrative resembles both absence and change at the same time: Mark it as insufficient information and do not select a root cause for it.
- The description says only "USB is broken": This is a conclusion, not a classifiable symptom. Ask for an anonymous symptom category instead.
- Someone provides a real path or hardware identifier: Stop copying and sharing it, then return the material to the controlled privacy process.
- Someone asked for a list of devices: Refuse. There are no enumeration or live viewing procedures for this chapter.
- Someone suggests trying drivers one by one: Refuse. A driver-family name is not a trial list.
- Someone suggested unplugging or rebooting: Refuse. This chapter does not trigger hardware or service actions.
- Someone wants to use bus to prove classification: Refuse. This chapter shall not connect, read, write or transmit any bus data.
FAQ
Advanced note: Initialization conversion is not device discovery evidence
The pinned initialization source describes how required USB values and interface settings are handled. This is a source-code responsibility; it neither confirms that a running environment found a candidate nor proves that converted values, drivers, or interfaces are available.
Does the lack of candidate items prove that the device does not exist?
No. It is a de-identified symptom category only and cannot identify hardware, connection, permissions, or environmental causes.
Can the old value and the new value be remembered when the path category changes?
No. Only abstract relationship changes are remembered; no actual values or device-specific differences are retained.
Can driver-category clues be used to select a driver?
No. The documented responsibility classification is not a compatibility list, nor is it a loading or trial recommendation.
Can I view the list of running devices and come back to fill in the form?
This chapter does not provide that procedure. Any live/running read-only viewing requires separate approval and does not extend the scope of this chapter.
Does the decision tree completion mean the USB problem is solved?
No. It only completes documentation classification, without proving device, driver, interface or bus functions.
Evidence and sources
Evidence class: source-bounded
Feature crosswalk: addon-init-configuration-lifecycle, upstream-driver-families, documented-driver-diagnostic-states
Pinned sources support only the documented scope. This page does not represent validation of any local environment, hardware, network, or KNX bus.