diff --git a/doc/simh.doc b/doc/simh.doc
index 6fda17d0..cfc7dbb1 100644
Binary files a/doc/simh.doc and b/doc/simh.doc differ
diff --git a/scp.c b/scp.c
index 2b23cebe..a5384b0c 100644
--- a/scp.c
+++ b/scp.c
@@ -13607,7 +13607,7 @@ static const char *debtab_nomatch = "DEBTAB_NOMATCH";
 const char *some_match = NULL;
 int32 offset = 0;
 
-if (dptr->debflags == 0)
+if (dptr->debflags == NULL)
     return debtab_none;
 
 dbits &= (dptr->dctrl | (uptr ? uptr->dctrl : 0));/* Look for just the bits that matched */
@@ -13676,6 +13676,8 @@ uint32 value, beforevalue, mask;
 for (fields=offset=0; bitdefs[fields].name; ++fields) {
     if (bitdefs[fields].offset == 0xffffffff)       /* fixup uninitialized offsets */
         bitdefs[fields].offset = offset;
+    else
+        offset = bitdefs[fields].offset;
     offset += bitdefs[fields].width;
     }
 for (i = fields-1; i >= 0; i--) {                   /* print xlation, transition */
@@ -13731,6 +13733,7 @@ if (sim_deb && dptr && (dptr->dctrl & dbits)) {
     sim_oline = saved_oline;                                            /* restore original socket */
     }
 }
+
 void sim_debug_bits(uint32 dbits, DEVICE* dptr, BITFIELD* bitdefs,
     uint32 before, uint32 after, int terminate)
 {
diff --git a/sim_defs.h b/sim_defs.h
index eae5c432..4b5ceb15 100644
--- a/sim_defs.h
+++ b/sim_defs.h
@@ -986,6 +986,7 @@ struct MEMFILE {
 /* Hidden Blob of Data - Only used for SAVE/RESTORE */
 #define SAVEDATA(nm,loc) \
     _REGDATANF(#nm,&(loc),0,8,0,1,NULL,NULL,0,sizeof(loc),sizeof(loc),SAVEDATA),(REG_HRO)
+#define STARTBIT             {"",  0x00000000, 0,  NULL, NULL}  /* Start at beginning bit */
 #define BIT(nm)              {#nm, 0xffffffff, 1,  NULL, NULL}  /* Single Bit definition */
 #define BITNC                {"",  0xffffffff, 1,  NULL, NULL}  /* Don't care Bit definition */
 #define BITF(nm,sz)          {#nm, 0xffffffff, sz, NULL, NULL}  /* Bit Field definition */
@@ -1073,6 +1074,7 @@ struct MEMFILE {
 /* Hidden Blob of Data - Only used for SAVE/RESTORE */
 #define SAVEDATA(nm,loc) \
     _REGDATANF("nm",&(loc),0,8,0,1,NULL,NULL,0,sizeof(loc),sizeof(loc)),SAVEDATA),(REG_HRO)
+#define STARTBIT             {"",   0x00000000, 0,  NULL, NULL} /* Start at beginning bit */
 #define BIT(nm)              {"nm", 0xffffffff, 1,  NULL, NULL} /* Single Bit definition */
 #define BITNC                {"",   0xffffffff, 1,  NULL, NULL} /* Don't care Bit definition */
 #define BITF(nm,sz)          {"nm", 0xffffffff, sz, NULL, NULL} /* Bit Field definition */