--- a/trace.c	Mon Jul 09 11:25:28 2018 +0900
+++ b/trace.c	Mon Jul 09 14:07:30 2018 +0900
@@ -100,7 +100,7 @@
 
                
 void setbreak(int adr,int count) ;
-void nexti(void);
+int nexti(void);
 
 void do_escape(void) {
         char s[80];
@@ -109,12 +109,12 @@
             bpskip--;
             int lpc = paddr(pcreg,mmu);
             BPTR *prev = &breakpoint;
-            for(BPTR b = breakpoint; b ; b=b->next, prev=prev->next) {
+            for(BPTR b = breakpoint; b ; prev=&b->next, b=b->next ) {
                 if (lpc==b->address) {
                     if (b->count==-1) {  // temporaly break point
                         BPTR next = b->next;
                         free(b);
-                        prev->next = next;
+                        *prev = next;
                         goto restart0;
                     }
                     if (b->count) b->count--;
@@ -191,11 +191,11 @@
                 if (s[1]) {
                    int trskip = getarg(s+1,0);
                    BPTR *prev = &breakpoint;
-                   for(BPTR bp = breakpoint; bp ; bp = bp->next) {
+                   for(BPTR bp = breakpoint; bp ; prev=&bp->next, bp = bp->next) {
                        if (trskip-- == 0) {
-                          BPTR next = b->next;
+                          BPTR next = bp->next;
                           free(bp);
-                          prev->next = next;
+                          *prev = next;
                           break;
                        }
                        prev = &bp->next;
@@ -348,49 +348,43 @@
   bp->next = breakpoint;
   breakpoint = bp;
   bp->count = count;
-  if (s[1]) {
-     char *next;
-     bp->laddr = getarg(s+0,&next);
-     bp->address = paddr((bp->laddr,&next),mmu);
-     if (next[0]) {
-         bp->count = getarg(next,&next);
-     }
-  } else {
-     bp->laddr = pcreg;
-     bp->address = paddr(pcreg,mmu);
-  }
+  bp->laddr = adr;
+  bp->address = paddr(adr,mmu);
 }
 
 int nexti(void) {
-    int op1 = phymem[mem1(pcreg)];
+#ifdef USE_MMU
+    int op1 = *mem0(phymem,pcreg,mmu);
+    int op2 = *mem0(phymem,pcreg+1,mmu);
+#else
+    int op1 = mem[pcreg];
+    int op2 = mem[pcreg+1];
+#endif
     int ofs = 0;
     switch(op1) {
         case 0x17: // LBSR
         case 0xbd: // JSR extended
-            ofs=3; beak;
+            ofs=3; break;
         case 0x10: // page2
             {
-                int op2 = phymem[mem1(pcreg+1)];
                 if (op2==0x3f) { // os9 system call
-                    ofs=3; beak;
+                    ofs=3; break;
                 }
             }
         case 0x11: // page3
             {
-                int op2 = phymem[mem1(pcreg+1)];
                 if (op2==0x3f) { // SWI3
-                    ofs=2; beak;
+                    ofs=2; break;
                 }
             }
         case 0x3f: // SWI
-            ofs=1; beak;
+            ofs=1; break;
         case 0x3c: // CWAI
         case 0x8d: // BSR
         case 0x9d: // JSR direct
-            ofs=2; beak;
+            ofs=2; break;
         case 0xad: // JSR index
             {
-                int op2 = phymem[mem1(pcreg+1)];
                 if (op2<0x80) ofs = 2;   // 5bit ofs
                 else switch (op2&0xf) { 
                     case 8: case 0xc:
@@ -403,8 +397,8 @@
             }
             break;
     }
-    if (ofs) setbreak(pc+ofs,-1);
-    retrun ofs;
+    if (ofs) setbreak(pcreg+ofs,-1);
+    return ofs;
 }