New user-facing features:
- `export connections <file>` writes a tabular dump of every wire pair:
connection, transform, left/right module/part/pin/signal/type/suspect,
mixed-types flag. Dispatch on extension: `.csv` (flat file) or `.ods`
(one sheet per connection). Any other extension shows an error and
writes nothing.
- Bare `export` (or dashboard `[x]`, or palette `export`) opens an
interactive file-picker dialog with a CSV/ODS toggle at the top.
Picking a filter rewrites the filename's extension. Last-used
directory and filename are remembered per-call-site.
- Two new CLI flags on the binary: `--source FILE` to run a script at
boot, `--restore FILE` to restore a snapshot at boot. Combinable.
Reusable infrastructure:
- `OdsWriter` (`src/imports/ods_writer.{hpp,cpp}`): minimal .ods writer
using libzip + pugixml (already in the build for the importer).
Multi-sheet workbook of string cells. ~180 lines, no new dep.
- Generic file-picker dialog (`screen_filedialog.cpp`): one Modal
reused for any "pick a path" interaction via
`OpenFileDialog(title, persist_key, default_filename, filters, cb)`.
Validates the picked extension against the filter whitelist;
unknown ones stay in the dialog with a status message. Persists
(dir, filename) per `persist_key`.
- Generic error modal (`screen_error.cpp`, `ShowError(msg)`): centred
red-titled popup, dismissable with Esc/Enter. Used by the export
failures (open-for-write, ODS save, unknown extension/kind);
ready for adoption elsewhere.
- Per-key path persistence (`SaveLastUsed`/`LoadLastUsed` in
`shell.cpp`): two-line file per key under the user-data dir.
- `UserDataDir()` extracted from the history path helper so the new
per-key persistence shares the same XDG/AppData logic.
- New help-screen topic "Export"; user-facing `doc/user/analysis.md`
gains an "Exporting" section; `DESIGN.md` gains a generics
section covering the dialog / error modal / persistence / ODS
writer; `DumpCommandsMd` now respects the `hidden` flag (the
`connect` alias no longer appears in the auto-gen reference).
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
7.2 KiB
essim — how the analysis classifies things
essim looks at signal names and the way pins are wired to decide
whether a net is a power rail, a ground, a diff pair, a
bus, etc. This page summarises those rules in plain language so you
know what to expect when you run analyze (the [a] shortcut on the
dashboard) or when you read the numbers on the home screen.
Nothing here mutates anything you cannot fix manually: every
inference can be overridden with set-signal-type, and the rules are
re-run on every load so the picture stays consistent with the
netlists currently in memory.
Signal type — Power / Gnd / Other
Every signal is classified into one of three buckets.
Gnd if the name matches one of:
GND, GROUND, EARTH, SHIELD, CHASSIS (or starts with any of
those followed by _). The name alone is enough — false positives
here are essentially nil.
Power is a two-stage decision:
-
The name has to suggest power — it contains
PWR,POWER,VCC,VDD,VEE,VSS,VBAT, or starts withVS_,VS3_,+5V-style or-12V-style prefixes. -
The wiring has to corroborate it. essim requires at least one of:
- the signal lands on 4 or more pins (a real rail goes to decouplers + ICs + connectors, so it almost always has many pads), or
- the name contains a voltage value —
3V3,5V,12V,0V9,5V0, etc. (anyVnext to a digit).
Hard floor: a signal touching fewer than 3 pins is never Power, even if both 1 and the voltage motif are present. Physically you cannot have a rail on 1 or 2 pads.
Other in every other case.
This rule deliberately rejects things that look like power but
aren't: PWR_OK (status), VSEL_0 (voltage select), VDD_SENSE
(sense feedback) — they all match step 1 but fail steps 2/3. The
analyze screen lists them under Suspect Power with the reason
attached (fan-out 1, no voltage etc.). Inspect, then either accept
the suspect status or force it back with set-signal-type.
NC (no-connect) pins
A pin is shown as (NC) in the explore detail when it has no signal
attached. essim distinguishes three reasons:
- Imported NC — the netlist explicitly says the pin is
unconnected (Mentor format: signal name
unconnectedorunconnected (by TERM); Altium format: the pin is simply omitted from every signal block). - Dropped singleton — after import, essim removes every signal
that touches exactly one pin. A net with a single endpoint cannot
carry signal anywhere, so the pin is detached and tagged. This
catches both intentional sentinels and the per-IC
NC_*labels that customers often put on dead pads. - Filled at connect — when you
connecttwo parts that don't agree on which pins exist (a Mentor part may have all pads, an Altium part only the wired ones), essim materialises the missing pads on the smaller side. They are unconnected locally on that module but are bridged to a real signal on the other module via the connection — so they do not count as orphans.
The dashboard's "NC" row summarises orphan counts (imported and dropped only; filled-at-connect pins are excluded). The analyze screen's "Types" tab adds a trailing line with the totals.
Signal groups
essim groups signals that share an obvious structural pattern. They are detected per module — a multi-card bus on the system is the BFS union of the per-module groups it touches.
Diff pair — two signals named STEM_P and STEM_N
(case-insensitive, _ required before the polarity letter). Both
halves must be present. Lone _P halves are flagged as orphans;
lone _N halves are not flagged (the _N suffix is overloaded
with active-low semantics — RESET_N, BOOTMODE_N — and flagging
them would flood the report).
Diff bus — at least two diff pairs whose stems share a common
prefix and only differ by a trailing index: MDI0_P/MDI0_N,
MDI1_P/MDI1_N, … → MDI[0..3]_P/N. Both STEMN and STEM_N
forms work (MDI0, PCIE_TX_0).
Bus — at least two signals with a common stem and a trailing
integer index. Two notations: DATA[0], DATA[1], … (bracketed)
or ADDR_0, ADDR_1, … (underscore — strict: an underscore is
required between the stem and the digits, so a name like
GETH_01_VDD12 is not a bus).
Anomalies are emitted alongside groups:
- Diff pair orphan: a
_Pwith no matching_N. - Diff bus gap: e.g.
MDI[0..3]hasMDI0,MDI1,MDI3(MDI2missing). - Bus gap: same idea on plain buses.
Internal Mentor net names that start with $ (like $N12345) are
skipped from every group/bus detection.
Issues reported by analyze
The Issues tab of the analyze screen aggregates everything that deserves attention:
| Tag | What it means |
|---|---|
[pin-role] |
A connector pin is typed (via set-connector-type) as Power or Gnd but the actual signal landing on it disagrees. |
[net-mix] |
A net bridged across modules carries both Power and Gnd signals — almost always a topology mistake. |
[diff-pair-orphan] |
STEM_P with no STEM_N in the same module. |
[bus-gap] |
A bus is missing one or more index values inside its range. |
[diff-bus-gap] |
A diff bus is missing one or more lane indices. |
Zero issues = the module passes every structural check essim knows how to run today.
Overrides
Every classification is advisory. To force a different type:
- Signal type: from the
explorescreen, press Enter on a signal entry → a popup lets you pickpower/gnd/other. The same popup also opens when you press Enter on a pin row in the parts detail (changes the pin's signal type) or on a net member row in the signal detail (works across modules). Or typeset-signal-type <module> <signal> <type>in the console (or from the palette). - Connector type: from
explorewithtype = parts, press Enter on a part to jump to the dedicatedset-connector-typescreen with that part pre-selected and the cursor on the type input. Theset-connector-typecommand also keeps working from the console / palette. - Connector type:
set-connector-type <module> <part> <connector-kind>(also via the dashboard[t]shortcut). This drives the pin role expectations, which feed thepin-rolecheck.
Overrides survive save/restore but are recomputed at every
load (i.e. the inference re-runs).
Exporting
Dump structured data to an external file:
export connections <file>— every wire pair, one row, with the signals and types on both sides plus asuspectflag (name says Power but the structural check disagreed) and amixedflag (both sides typed but disagreeing).- The dashboard's
[x]shortcut, theexportcommand without arguments, or the palette entryexport: opens an interactive file-picker dialog. A small toggle at the top of the dialog lets you pick the format — CSV (flat, one row per wire) or ODS (one sheet per connection, opens directly in LibreOffice / Excel). The dialog remembers the directory and filename you used last so the next export resumes from there. - Inline scriptable form:
export connections /path/foo.csv(or.ods). Unknown extensions raise an error popup.