From 44fd33ea7d3d3b94221a52d8f1668f79e533410f Mon Sep 17 00:00:00 2001
From: Holger Vogt <holger.vogt@uni-due.de>
Date: Sun, 8 Feb 2026 15:47:04 +0100
Subject: [PATCH] Add a command 'degsim' to reset the circuit, remove the
 monitors, and add the degradation model to each degraded device. Use function
 preparedegsim() to add the model with parameters from degdatahash.

---
 .../degradation/Inverter_degmon_new_2.cir     |  2 ++
 src/frontend/commands.c                       |  6 +++++-
 src/frontend/inp.c                            | 16 +++++++++++++++-
 src/frontend/inpdeg.c                         | 10 ++++++++++
 src/frontend/runcoms2.c                       | 19 +++++++++++++++++++
 src/frontend/runcoms2.h                       |  1 +
 6 files changed, 52 insertions(+), 2 deletions(-)

diff --git a/examples/degradation/Inverter_degmon_new_2.cir b/examples/degradation/Inverter_degmon_new_2.cir
index 1b8c1b27d..51870e30e 100644
--- a/examples/degradation/Inverter_degmon_new_2.cir
+++ b/examples/degradation/Inverter_degmon_new_2.cir
@@ -32,6 +32,8 @@ pre_osdi ../lib/ngspice/psp103_nqs.osdi
 pre_osdi ../lib/ngspice/psp103.osdi
 run
 rusage
+degsim
+run
 *set nolegend
 set xbrushwidth=3
 plot xnot1.mon1 xnot2.mon1 xnot3.mon1
diff --git a/src/frontend/commands.c b/src/frontend/commands.c
index 3de1ba6fb..41a127c34 100644
--- a/src/frontend/commands.c
+++ b/src/frontend/commands.c
@@ -448,7 +448,11 @@ struct comm spcp_coms[] = {
     { "reset", com_rset, TRUE, TRUE,
       { 0, 0, 0, 0 }, E_DEFHMASK, 0, 0,
       NULL,
-      ": Terminate a simulation after a breakpoint (formerly 'end')." } ,
+      ": Remove current ciuit, reload circuit from internal storage." } ,
+    { "degsim", com_degsim, TRUE, TRUE,
+      { 0, 0, 0, 0 }, E_DEFHMASK, 0, 0,
+      NULL,
+      ": Remove current circuit, reload and modify circuit." } ,
     { "run", com_run, TRUE, TRUE,
       { 0, 0, 0, 0 }, E_DEFHMASK, 0, 1,
       NULL,
diff --git a/src/frontend/inp.c b/src/frontend/inp.c
index e17977c78..79a5cc016 100644
--- a/src/frontend/inp.c
+++ b/src/frontend/inp.c
@@ -64,6 +64,8 @@ static void rem_unused_mos_models(struct card* deck);
 extern void com_optran(wordlist * wl);
 extern void tprint(struct card *deck);
 
+static bool wantdegsim = FALSE;
+extern int preparedegsim(struct card* deck);
 
 //void inp_source_recent(void);
 //void inp_mc_free(void);
@@ -1091,7 +1093,15 @@ inp_spsource(FILE *fp, bool comfile, char *filename, bool intfile)
            if (newcompat.hs || newcompat.spe)
               rem_unused_mos_models(deck->nextcard);
 #endif
-            /* Parsing the circuit 5.
+           /* If compatmode is de and degsim is set by command 'degsim',
+              translate the netlist by removing the monitors and adding the
+              extra degradation elements. */
+           if (wantdegsim && newcompat.de) {
+               wantdegsim = FALSE;
+               preparedegsim(deck);
+           }
+
+           /* Parsing the circuit 5.
                This is the next major step:
                load deck into ft_curckt -- the current circuit. */
             if(inp_dodeck(deck, tt, wl_first, FALSE, options, filename) != 0)
@@ -2679,6 +2689,10 @@ struct mlist {
     bool checked;
 };
 
+void setdegsim(void) {
+    wantdegsim = TRUE;
+}
+
 #ifdef REM_UNUSED
 /* Finally get rid of unused MOS models */
 static void rem_unused_mos_models(struct card* deck) {
diff --git a/src/frontend/inpdeg.c b/src/frontend/inpdeg.c
index d33ff436b..605f29d0c 100644
--- a/src/frontend/inpdeg.c
+++ b/src/frontend/inpdeg.c
@@ -15,6 +15,8 @@ License: Modified BSD
 
 #include "inpcom.h"
 
+int preparedegsim(struct card* deck);
+
 /* maximum number of model parameters */
 #define DEGPARAMAX 64
 /* maximum number of models */
@@ -296,3 +298,11 @@ int remsqrbra(struct card* deck) {
     }
     return 0;
 }
+
+/* Remove the degradation monitors.
+   Add current measurement, delta_vg and current source.
+   Use the data retrieved from degdatahash */
+int preparedegsim(struct card* deck) {
+    fprintf(stdout, "Note: degradation simulation prepared.\n");
+    return 0;
+}
diff --git a/src/frontend/runcoms2.c b/src/frontend/runcoms2.c
index baf43ee79..e06d3501d 100644
--- a/src/frontend/runcoms2.c
+++ b/src/frontend/runcoms2.c
@@ -36,6 +36,8 @@ extern void line_free_x(struct card *deck, bool recurse);
 extern INPmodel *modtab;
 extern NGHASHPTR modtabhash;
 
+extern void setdegsim(void);
+
 #ifdef SHARED_MODULE
 extern void exec_controls(wordlist *newcontrols);
 #endif
@@ -169,6 +171,23 @@ com_resume(wordlist *wl)
 }
 
 
+/* Throw out the circuit struct and recreate it from the deck. */
+void
+com_degsim(wordlist* wl)
+{
+    NG_IGNORE(wl);
+
+    if (ft_curckt == NULL) {
+        fprintf(cp_err, "Warning: there is no circuit loaded.\n");
+        fprintf(cp_err, "    Command 'reset' is ignored.\n");
+        return;
+    }
+    com_remcirc(NULL);
+    setdegsim();
+    inp_source_recent();
+}
+
+
 /* Throw out the circuit struct and recreate it from the deck. */
 void
 com_rset(wordlist *wl)
diff --git a/src/frontend/runcoms2.h b/src/frontend/runcoms2.h
index 957a64ece..7c52e5776 100644
--- a/src/frontend/runcoms2.h
+++ b/src/frontend/runcoms2.h
@@ -9,5 +9,6 @@
 void com_resume(wordlist *wl);
 void com_rset(wordlist *wl);
 void com_remcirc(wordlist *wl);
+void com_degsim(wordlist* wl);
 
 #endif