Pins: replace expected_signal_type field with a model-derived PinSpec

Introduce PinSpec (function/direction/pad/source) as the "expected" half of
pin verification, and make Pin::expected_signal_type() a derived accessor over
spec.function. pin_role() now returns a PinSpec; the connector layout (and,
later, BSDL) feed the same structure.

Pure refactor, behaviour-preserving: vpx_3u_role is still a stub, so every pin
maps to Other exactly as before. The new `pad` field will carry the BSDL
physical pin; direction/function will unlock contention/undriven/NC checks.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/system/pin_role.cpp

@@ -40,13 +40,15 @@ bool parse_pin(const std::string &s, char &col, int &row) {
 
 }  // namespace
 
-SignalType pin_role(const std::string &kind, const std::string &pin_name)
+PinSpec pin_role(const std::string &kind, const std::string &pin_name)
 {
-    if (kind.empty()) return SignalType::Other;
+    PinSpec spec;
+    if (kind.empty()) return spec;
 
     char col; int row;
-    if (!parse_pin(pin_name, col, row)) return SignalType::Other;
+    if (!parse_pin(pin_name, col, row)) return spec;
 
+    SignalType st = SignalType::Other;
     int idx = -1;
     bool is_vpx_3u = false;
     if (kind.rfind("vpx-3u-bkp-p", 0) == 0
@@ -55,9 +57,11 @@ SignalType pin_role(const std::string &kind, const std::string &pin_name)
         const std::string suffix = kind.substr(kind.size() - 1);
         try { idx = std::stoi(suffix); } catch (const std::exception &) {}
     }
-    if (is_vpx_3u && idx >= 0) return vpx_3u_role(col, row, idx);
+    if (is_vpx_3u && idx >= 0) st = vpx_3u_role(col, row, idx);
 
-    return SignalType::Other;
+    spec.function = function_from_signal_type(st);
+    spec.source   = SpecSource::ConnectorModel;
+    return spec;
 }
 
 std::vector<std::string> pin_layout(const std::string &kind)

src/system/pin_role.hpp

@@ -1,21 +1,21 @@
 #ifndef _PIN_ROLE_HPP_
 #define _PIN_ROLE_HPP_
 
-#include "signal_type.hpp"
+#include "pin_spec.hpp"
 
 #include <string>
 #include <vector>
 
 class Part;
 
-// For a given connector type and pin position, return the expected SignalType
+// For a given connector type and pin position, return the expected PinSpec
-// (Power / GndShield / Other). Used at `set-connector-type` to populate each pin's
+// (function/direction/pad + source). Used at `set-connector-type` to populate
-// `expected_signal_type`, then later by `verify` to flag mismatches between
+// each pin's `spec`, then later by `verify` to flag mismatches between the
-// the connector's expectation and the actual signal's inferred/declared type.
+// connector's expectation and the actual signal's inferred/declared type.
 //
-// Returns SignalType::Other for unknown connector types or unmatched pins —
+// Returns a default PinSpec (function Unknown, source None) for unknown
-// caller can treat that as "no expectation, no constraint".
+// connector types or unmatched pins — i.e. "no expectation, no constraint".
-SignalType pin_role(const std::string &connector_type,
+PinSpec pin_role(const std::string &connector_type,
                  const std::string &pin_name);
 
 // Canonical full pin-name list for the connector type (e.g. for VPX 3U,

src/system/pin_spec.hpp

@@ -0,0 +1,54 @@
+#ifndef _PIN_SPEC_HPP_
+#define _PIN_SPEC_HPP_
+
+#include "signal_type.hpp"
+
+#include <string>
+
+#pragma once
+
+// Direction of a pin as seen from the component (port/BSDL semantics).
+enum class PinDirection { Unknown, In, Out, Bidir, Passive, Power };
+
+// Functional role of a pin. Richer than SignalType (which classifies *nets*):
+// this classifies the *pin* itself and carries the TAP roles JTAG checks need.
+enum class PinFunction {
+    Unknown, Power, Ground, Signal, Clock, NoConnect,
+    JtagTdi, JtagTdo, JtagTms, JtagTck, JtagTrst
+};
+
+// Where a pin's expected attributes came from. Lets verify report conflicts and
+// lets a user override win over a model-derived value.
+enum class SpecSource { None, Imported, ConnectorModel, Bsdl, Inferred, UserOverride };
+
+// Expected, model-derived attributes of a pin (from a connector layout, a BSDL
+// model, …). The "expected" half of the expected-vs-observed verify duality;
+// the "observed" half stays Pin::signal() + the net + inference.
+struct PinSpec {
+    PinFunction  function  = PinFunction::Unknown;
+    PinDirection direction = PinDirection::Unknown;
+    std::string  pad;                    ///< Physical terminal (package ball/pin); "" if unknown.
+    SpecSource   source    = SpecSource::None;
+};
+
+// PinFunction -> the net SignalType a pin of that function expects to sit on.
+inline SignalType to_signal_type(PinFunction f)
+{
+    switch (f) {
+    case PinFunction::Power:  return SignalType::Power;
+    case PinFunction::Ground: return SignalType::GndShield;
+    default:                  return SignalType::Other;
+    }
+}
+
+// Coarse SignalType -> PinFunction, used when a model only yields a SignalType.
+inline PinFunction function_from_signal_type(SignalType t)
+{
+    switch (t) {
+    case SignalType::Power:     return PinFunction::Power;
+    case SignalType::GndShield: return PinFunction::Ground;
+    default:                    return PinFunction::Unknown;
+    }
+}
+
+#endif // _PIN_SPEC_HPP_

src/system/pins.cpp

@@ -3,8 +3,12 @@
 #include "signals.hpp"
 
 Pin::Pin(std::string name)
-    : SystemElement(name), sig(nullptr), prnt(nullptr),
+    : SystemElement(name), sig(nullptr), prnt(nullptr) {};
-      expected_signal_type(SignalType::Other) {};
+
+SignalType Pin::expected_signal_type() const
+{
+    return to_signal_type(spec.function);
+}
 
 const char *nc_origin_tag(NcOrigin o) {
     switch (o) {

src/system/pins.hpp

@@ -2,6 +2,7 @@
 #define _PINS_HPP_
 
 #include "signal_type.hpp"
+#include "pin_spec.hpp"
 #include "syselmts.hpp"
 
 #pragma once
@@ -29,11 +30,13 @@ class Pin : public SystemElement
 public:
     Pin(std::string name);
     Part *prnt; ///< Pointer to the parent part.
-    SignalType expected_signal_type;  ///< Set from connector_type at set-connector-type.
+    PinSpec spec;  ///< Expected, model-derived attributes (connector layout / BSDL). Not persisted; re-applied from the model.
     NcOrigin nc_origin = NcOrigin::None;
     bool connected();
     Signal *signal() const { return sig; }
     void connect(Signal *signal);
+    // Net type this pin expects, derived from spec.function (Power/GndShield/Other).
+    SignalType expected_signal_type() const;
 };
 
 class Pins : public SystemElementContainer<Pin>

src/tui/commands.cpp

@@ -235,7 +235,7 @@ void Tui::RegisterCommands() {
                 for (auto &nkv : *prt) {
                     Pin *pin = nkv.second;
                     ++checked;
-                    SignalType expected = pin->expected_signal_type;
+                    SignalType expected = pin->expected_signal_type();
                     if (expected == SignalType::Other) continue;
                     Signal *s = pin->signal();
                     SignalType actual = s ? s->type : SignalType::Other;
@@ -440,7 +440,7 @@ void Tui::RegisterCommands() {
             prt->connector_type = args[2];
             int filled = FillPartFromLayout(prt, args[2]);
             for (auto &kv : *prt)
-                kv.second->expected_signal_type = pin_role(args[2], kv.first);
+                kv.second->spec = pin_role(args[2], kv.first);
             Print(mod->name + "/" + prt->name + ": connector_type = "
                   + (args[2].empty() ? "(none)" : args[2]));
             if (filled > 0)
@@ -648,7 +648,7 @@ void Tui::RegisterCommands() {
                 for (auto &nkv : *sp) {
                     Pin *sn = nkv.second;
                     Pin *dn = new Pin(sn->name);
-                    dn->expected_signal_type = sn->expected_signal_type;
+                    dn->spec = sn->spec;
                     dn->nc_origin = sn->nc_origin;
                     dp->add(dn);
                     if (sn->signal()) {

src/tui/screen_analyze.cpp

@@ -64,7 +64,7 @@ Component Tui::BuildAnalyzeScreen() {
                 for (auto &nkv : *prt) {
                     Pin *pin = nkv.second;
                     ++n_typed_pins;
-                    SignalType expected = pin->expected_signal_type;
+                    SignalType expected = pin->expected_signal_type();
                     if (expected == SignalType::Other) continue;
                     Signal *s = pin->signal();
                     SignalType actual = s ? s->type : SignalType::Other;

src/tui/screen_dashboard.cpp

@@ -83,7 +83,7 @@ Component Tui::BuildDashboardScreen() {
               for (auto &nkv : *prt) {
                   Pin *pin = nkv.second;
                   ++n_typed_pins;
-                  SignalType expected = pin->expected_signal_type;
+                  SignalType expected = pin->expected_signal_type();
                   if (expected == SignalType::Other) continue;
                   Signal *s = pin->signal();
                   SignalType actual = s ? s->type : SignalType::Other;

src/tui/screen_settype.cpp

@@ -69,7 +69,7 @@ Component Tui::BuildSettypeScreen() {
             }
             prt->connector_type = settype_type;
             for (auto &kv : *prt)
-                kv.second->expected_signal_type = pin_role(settype_type, kv.first);
+                kv.second->spec = pin_role(settype_type, kv.first);
             std::string msg = mod->name + "/" + prt->name + " = "
                             + (settype_type.empty() ? "(none)" : settype_type);
             settype_status = "applied: " + msg;