diff --git a/nanovna.h b/nanovna.h
index e6b719f..378e1ab 100644
--- a/nanovna.h
+++ b/nanovna.h
@@ -116,7 +116,7 @@ typedef struct {
   uint8_t polar;
 } trace_t;
 
-//extern trace_t trace[TRACES_MAX];
+extern trace_t trace[TRACES_MAX];
 
 typedef struct {
   int enabled;
@@ -138,6 +138,8 @@ void draw_cell_all(void);
 
 void draw_cal_status(void);
 
+void markmap_all_markers(void);
+
 
 /*
  * main.c
diff --git a/plot.c b/plot.c
index c8944f2..c0d5c38 100644
--- a/plot.c
+++ b/plot.c
@@ -112,45 +112,191 @@ circle_inout(int x, int y, int r)
 }
 
 
-#define POLAR_CENTER_X 146
-#define POLAR_CENTER_Y 116
-#define POLAR_RADIUS 116
+#define P_CENTER_X 146
+#define P_CENTER_Y 116
+#define P_RADIUS 116
 
+int
+polar_grid(int x, int y)
+{
+  int c = grid_color;
+  int d;
+
+  // offset to center
+  x -= P_CENTER_X;
+  y -= P_CENTER_Y;
+
+  // outer circle
+  d = circle_inout(x, y, P_RADIUS);
+  if (d < 0) return 0;
+  if (d == 0) return c;
+
+  // vertical and horizontal axis
+  if (x == 0 || y == 0)
+    return c;
+
+  d = circle_inout(x, y, P_RADIUS / 5);
+  if (d == 0) return c;
+  if (d > 0) return 0;
+
+  d = circle_inout(x, y, P_RADIUS * 2 / 5);
+  if (d == 0) return c;
+  if (d > 0) return 0;
+
+  // cross sloping lines
+  if (x == y || x == -y)
+    return c;
+
+  d = circle_inout(x, y, P_RADIUS * 3 / 5);
+  if (d == 0) return c;
+  if (d > 0) return 0;
+
+  d = circle_inout(x, y, P_RADIUS * 4 / 5);
+  if (d == 0) return c;
+  return 0;
+}
+
+/*
+ * Constant Resistance circle: (u - r/(r+1))^2 + v^2 = 1/(r+1)^2
+ * Constant Reactance circle:  (u - 1)^2 + (v-1/x)^2 = 1/x^2
+ */
 int
 smith_grid(int x, int y)
 {
-  int d = circle_inout(x-146, y-116, 116);
   int c = grid_color;
+  int d;
+
+  // offset to center
+  x -= P_CENTER_X;
+  y -= P_CENTER_Y;
+  
+  // outer circle
+  d = circle_inout(x, y, P_RADIUS);
   if (d < 0)
     return 0;
-  else if (d == 0)
+  if (d == 0)
     return c;
-  x -= 146+116;
-  y -= 116;
-  
+
+  // shift circle center to right origin
+  x -= P_RADIUS;
+
+  // Constant Reactance Circle: 2j : R/2 = 58
   if (circle_inout(x, y+58, 58) == 0)
     return c;
   if (circle_inout(x, y-58, 58) == 0)
     return c;
+
+  // Constant Resistance Circle: 3 : R/4 = 29
   d = circle_inout(x+29, y, 29);
   if (d > 0) return 0;
   if (d == 0) return c;
+
+  // Constant Reactance Circle: 1j : R = 116
   if (circle_inout(x, y+116, 116) == 0)
     return c;
   if (circle_inout(x, y-116, 116) == 0)
     return c;
+
+  // Constant Resistance Circle: 1 : R/2 = 58
   d = circle_inout(x+58, y, 58);
   if (d > 0) return 0;
   if (d == 0) return c;
+
+  // Constant Reactance Circle: 1/2j : R*2 = 232
   if (circle_inout(x, y+232, 232) == 0)
     return c;
   if (circle_inout(x, y-232, 232) == 0)
     return c;
+
+  // Constant Resistance Circle: 1/3 : R*3/4 = 87
   if (circle_inout(x+87, y, 87) == 0)
     return c;
   return 0;
 }
 
+int
+smith_grid2(int x, int y, float scale)
+{
+  int c = grid_color;
+  int d;
+
+  // offset to center
+  x -= P_CENTER_X;
+  y -= P_CENTER_Y;
+  
+  // outer circle
+  d = circle_inout(x, y, P_RADIUS);
+  if (d < 0)
+    return 0;
+  if (d == 0)
+    return c;
+
+  // shift circle center to right origin
+  x -= P_RADIUS * scale;
+
+  // Constant Reactance Circle: 2j : R/2 = 58
+  if (circle_inout(x, y+58*scale, 58*scale) == 0)
+    return c;
+  if (circle_inout(x, y-58*scale, 58*scale) == 0)
+    return c;
+#if 0
+  // Constant Resistance Circle: 3 : R/4 = 29
+  d = circle_inout(x+29*scale, y, 29*scale);
+  if (d > 0) return 0;
+  if (d == 0) return c;
+  d = circle_inout(x-29*scale, y, 29*scale);
+  if (d > 0) return 0;
+  if (d == 0) return c;
+#endif
+
+  // Constant Reactance Circle: 1j : R = 116
+  if (circle_inout(x, y+116*scale, 116*scale) == 0)
+    return c;
+  if (circle_inout(x, y-116*scale, 116*scale) == 0)
+    return c;
+
+  // Constant Resistance Circle: 1 : R/2 = 58
+  d = circle_inout(x+58*scale, y, 58*scale);
+  if (d > 0) return 0;
+  if (d == 0) return c;
+  d = circle_inout(x-58*scale, y, 58*scale);
+  if (d > 0) return 0;
+  if (d == 0) return c;
+
+  // Constant Reactance Circle: 1/2j : R*2 = 232
+  if (circle_inout(x, y+232*scale, 232*scale) == 0)
+    return c;
+  if (circle_inout(x, y-232*scale, 232*scale) == 0)
+    return c;
+
+#if 0
+  // Constant Resistance Circle: 1/3 : R*3/4 = 87
+  d = circle_inout(x+87*scale, y, 87*scale);
+  if (d > 0) return 0;
+  if (d == 0) return c;
+  d = circle_inout(x+87*scale, y, 87*scale);
+  if (d > 0) return 0;
+  if (d == 0) return c;
+#endif
+
+  // Constant Resistance Circle: 0 : R
+  d = circle_inout(x+P_RADIUS*scale, y, P_RADIUS*scale);
+  if (d > 0) return 0;
+  if (d == 0) return c;
+  d = circle_inout(x-P_RADIUS*scale, y, P_RADIUS*scale);
+  if (d > 0) return 0;
+  if (d == 0) return c;
+
+  // Constant Resistance Circle: -1/3 : R*3/2 = 174
+  d = circle_inout(x+174*scale, y, 174*scale);
+  if (d > 0) return 0;
+  if (d == 0) return c;
+  d = circle_inout(x-174*scale, y, 174*scale);
+  //if (d > 0) return 0;
+  if (d == 0) return c;
+  return 0;
+}
+
 #if 0
 int
 rectangular_grid(int x, int y)
@@ -493,6 +639,12 @@ is_mapmarked(int x, int y)
   return (markmap[0][y] & bit) || (markmap[1][y] & bit);
 }
 
+static inline void
+markmap_upperarea(void)
+{
+  markmap[current_mappage][0] |= 0xffff;
+}
+
 static void
 swap_markmap(void)
 {
@@ -779,9 +931,9 @@ markmap_all_markers(void)
       continue;
     markmap_marker(i);
   }
+  markmap_upperarea();
 }
 
-
 int area_width = WIDTH;
 int area_height = HEIGHT;
 
@@ -820,6 +972,8 @@ draw_cell(int m, int n)
     for (x = 0; x < w; x++) {
       //uint16_t c = rectangular_grid(x+x0, y+y0);
       uint16_t c = smith_grid(x+x0, y+y0);
+      //uint16_t c = smith_grid2(x+x0, y+y0, 0.5);
+      //uint16_t c = polar_grid(x+x0, y+y0);
       spi_buffer[y * w + x] |= c;
     }
   }
diff --git a/tlv320aic3204.c b/tlv320aic3204.c
index e1bc9d1..de34b07 100644
--- a/tlv320aic3204.c
+++ b/tlv320aic3204.c
@@ -168,7 +168,7 @@ const uint8_t adc_filter_config[] = {
   0x81, 0x1e, 0xf9, 0x00,
   0 /* sentinel */
 };
-#elsif 0
+#elif 0
 /* bb, aa = signal.ellip(2, 0.1, 100, (4500.0/24000, 5500.0/24000), 'bandpass') */
 const uint8_t adc_filter_config[] = {
   /* len, page, reg, data.... */
diff --git a/ui.c b/ui.c
index 957f1c3..dec8842 100644
--- a/ui.c
+++ b/ui.c
@@ -24,10 +24,11 @@
 #include <stdlib.h>
 
 struct {
-    enum { CHANNEL, FREQ, VOLUME, MOD, AGC, RFGAIN, DGAIN, MODE_MAX } mode;
-	int digit; /* 0~5 */
+  int digit; /* 0~5 */
+  int current_trace; /* 0..3 */
 } uistat;
 
+
 #define NO_EVENT					0
 #define EVT_BUTTON_SINGLE_CLICK		0x01
 #define EVT_BUTTON_DOUBLE_CLICK		0x02
@@ -169,7 +170,8 @@ enum {
   MT_BLANK,
   MT_SUBMENU,
   MT_CALLBACK,
-  MT_CANCEL
+  MT_CANCEL,
+  MT_CLOSE
 };
 
 typedef void (*menuaction_cb_t)(int item);
@@ -178,7 +180,6 @@ typedef void (*menuaction_cb_t)(int item);
 static void menu_move_back(void);
 
 
-
 static void
 menu_cal_cb(int item)
 {
@@ -214,7 +215,7 @@ menu_caldone_cb(int item)
 static void
 menu_recall_cb(int item)
 {
-  if (item < 0 || item > 5)
+  if (item < 0 || item >= 5)
     return;
   if (caldata_recall(item) == 0) {
     ui_status = FALSE;
@@ -224,6 +225,51 @@ menu_recall_cb(int item)
   }
 }
 
+static void
+menu_trace_cb(int item)
+{
+  if (item < 0 || item >= 4)
+    return;
+  uistat.current_trace = item;
+}
+
+static void
+menu_format_cb(int item)
+{
+  trace[uistat.current_trace].type = item;
+}
+
+static void 
+elect_active_marker(void)
+{
+  int i;
+  for (i = 0; i < 4; i++)
+    if (markers[i].enabled) {
+      active_marker = i;
+      return;
+    }
+  active_marker = -1;
+}
+
+static void
+menu_marker_cb(int item)
+{
+  if (item < 0 || item >= 4)
+    return;
+
+  if (active_marker == item) {
+    markers[active_marker].enabled = FALSE;
+    elect_active_marker();
+  } else {
+    active_marker = item;
+    markers[active_marker].enabled = TRUE;
+  }
+  if (active_marker >= 0)
+    redraw_marker(active_marker, TRUE);
+  ui_status = FALSE;
+  ui_hide();
+}
+
 typedef struct {
   uint8_t type;
   char *label;
@@ -241,6 +287,43 @@ const menuitem_t menu_cal[] = {
   { MT_NONE, NULL, NULL } // sentinel
 };
 
+const menuitem_t menu_trace[] = {
+  { MT_CALLBACK, "0", menu_trace_cb },
+  { MT_CALLBACK, "1", menu_trace_cb },
+  { MT_CALLBACK, "2", menu_trace_cb },
+  { MT_CALLBACK, "3", menu_trace_cb },
+  { MT_CANCEL, "BACK", NULL },
+  { MT_NONE, NULL, NULL } // sentinel
+};
+
+const menuitem_t menu_format[] = {
+  { MT_CALLBACK, "LOGMAG", menu_format_cb },
+  { MT_CALLBACK, "PHASE", menu_format_cb },
+  { MT_CALLBACK, "SMITH", menu_format_cb },
+  { MT_CALLBACK, "ADMIT", menu_format_cb },
+  { MT_CALLBACK, "DELAY", menu_format_cb },
+  { MT_CALLBACK, "SWR", menu_format_cb },
+  { MT_CANCEL, "BACK", NULL },
+  { MT_NONE, NULL, NULL } // sentinel
+};
+
+const menuitem_t menu_display[] = {
+  { MT_SUBMENU, "TRACE", menu_trace },
+  { MT_SUBMENU, "FORMAT", menu_format },
+  { MT_SUBMENU, "SCALE", menu_format },
+  { MT_CANCEL, "BACK", NULL },
+  { MT_NONE, NULL, NULL } // sentinel
+};
+
+const menuitem_t menu_marker[] = {
+  { MT_CALLBACK, "1", menu_marker_cb },
+  { MT_CALLBACK, "2", menu_marker_cb },
+  { MT_CALLBACK, "3", menu_marker_cb },
+  { MT_CALLBACK, "4", menu_marker_cb },
+  { MT_CANCEL, "BACK", NULL },
+  { MT_NONE, NULL, NULL } // sentinel
+};
+
 const menuitem_t menu_recall[] = {
   { MT_CALLBACK, "0", menu_recall_cb },
   { MT_CALLBACK, "1", menu_recall_cb },
@@ -253,8 +336,10 @@ const menuitem_t menu_recall[] = {
 
 const menuitem_t menu_top[] = {
   { MT_SUBMENU, "CAL", menu_cal },
+  { MT_SUBMENU, "DISPLAY", menu_display },
+  { MT_SUBMENU, "MARKER", menu_marker },
   { MT_SUBMENU, "RECALL", menu_recall },
-  { MT_CANCEL, "BACK", NULL },
+  { MT_CLOSE, "CLOSE", NULL },
   { MT_NONE, NULL, NULL } // sentinel
 };
 
@@ -288,6 +373,7 @@ void menu_invoke(int selection)
   switch (menu->type) {
   case MT_NONE:
   case MT_BLANK:
+  case MT_CLOSE:
     ui_status = FALSE;
     ui_hide();
     break;
@@ -422,7 +508,8 @@ ui_process(void)
           }
           status = btn_wait_release();
         } while (status != 0);
-        redraw_marker(active_marker, TRUE);
+        if (active_marker >= 0)
+          redraw_marker(active_marker, TRUE);
       }
     }
   }