diff --git a/examples/targetSel/include/README b/examples/targetSel/include/README
new file mode 100644
index 00000000..194dcd43
--- /dev/null
+++ b/examples/targetSel/include/README
@@ -0,0 +1,39 @@
+
+This directory is intended for project header files.
+
+A header file is a file containing C declarations and macro definitions
+to be shared between several project source files. You request the use of a
+header file in your project source file (C, C++, etc) located in `src` folder
+by including it, with the C preprocessing directive `#include'.
+
+```src/main.c
+
+#include "header.h"
+
+int main (void)
+{
+ ...
+}
+```
+
+Including a header file produces the same results as copying the header file
+into each source file that needs it. Such copying would be time-consuming
+and error-prone. With a header file, the related declarations appear
+in only one place. If they need to be changed, they can be changed in one
+place, and programs that include the header file will automatically use the
+new version when next recompiled. The header file eliminates the labor of
+finding and changing all the copies as well as the risk that a failure to
+find one copy will result in inconsistencies within a program.
+
+In C, the usual convention is to give header files names that end with `.h'.
+It is most portable to use only letters, digits, dashes, and underscores in
+header file names, and at most one dot.
+
+Read more about using header files in official GCC documentation:
+
+* Include Syntax
+* Include Operation
+* Once-Only Headers
+* Computed Includes
+
+https://gcc.gnu.org/onlinedocs/cpp/Header-Files.html
diff --git a/examples/targetSel/targetSel/targetSel.ino b/examples/targetSel/targetSel/targetSel.ino
new file mode 100644
index 00000000..9c3b3fb3
--- /dev/null
+++ b/examples/targetSel/targetSel/targetSel.ino
@@ -0,0 +1,164 @@
+/********************
+Arduino generic menu system
+
+Rui Azevedo - ruihfazevedo(@rrob@)gmail.com
+
+output: Serial
+input: Serial
+
+user defined array menu (userMenu plugin)
+*/
+
+#include <menu.h>
+#include <menuIO/serialOut.h>
+#include <menuIO/serialIn.h>
+#include <plugin/userMenu.h>
+
+using namespace Menu;
+
+#define MAX_DEPTH 4
+
+enum SelTest {Zero=0,One,Two};
+enum ChooseTest {First=1,Second=2,Third=3,Last=-1};
+constexpr int dataSz=3;
+constexpr int nameSz=20;
+
+struct Data {
+  char name[nameSz+1]="<name>              ";
+  bool valid=0;
+  SelTest selTest=Zero;
+  ChooseTest chooseTest=First;
+  //how to copy this data, being a simple data c++ will generate this for you
+  // Data& operator=(Data& o){
+  //   strcpy(name,o.name);
+  //   valid=o.valid;
+  //   selTest=o.selTest;
+  //   chooseTest=o.chooseTest;
+  //   return o;
+  // }
+};
+
+Data myTargets[dataSz];//our data
+//a temp. to be edited
+//the data type must have assignment operator
+//because we will later on move data back and forth between the actual data and this template
+//menu edit is wired to this temp. and menu eventd will deal with the copy-call
+Data target;
+
+
+char* constMEM alphaNum MEMMODE=" 0123456789.ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz,\\|!\"#$%&/()=?~*^+-{}[]€";
+char* constMEM alphaNumMask[] MEMMODE={alphaNum};
+
+TOGGLE(target.valid,editValid,"Valid: ",doNothing,noEvent,noStyle//,doExit,enterEvent,noStyle
+  ,VALUE("On",HIGH,doNothing,noEvent)
+  ,VALUE("Off",LOW,doNothing,noEvent)
+);
+
+SELECT(target.selTest,selMenu,"Select",doNothing,noEvent,noStyle
+  ,VALUE("Zero",Zero,doNothing,noEvent)
+  ,VALUE("One",One,doNothing,noEvent)
+  ,VALUE("Two",Two,doNothing,noEvent)
+);
+
+CHOOSE(target.chooseTest,chooseMenu,"Choose",doNothing,noEvent,noStyle
+  ,VALUE("First",First,doNothing,noEvent)
+  ,VALUE("Second",Second,doNothing,noEvent)
+  ,VALUE("Third",Third,doNothing,noEvent)
+  ,VALUE("Last",Last,doNothing,noEvent)
+);
+
+result saveTarget(eventMask e,navNode& nav) {
+  _trace(MENU_DEBUG_OUT<<"saveTarget"<<endl);
+  idx_t n=nav.root->path[nav.root->level-1].sel;//get selection of previous level
+  myTargets[n]=target;
+  return quit;
+}
+
+//if you want to print the recird name as the title,
+//then you MUST create a customized print menu to replace this default one
+MENU(targetEdit,"Target edit",doNothing,noEvent,wrapStyle
+  ,EDIT("Name",target.name,alphaNumMask,doNothing,noEvent,noStyle)
+  ,SUBMENU(editValid)
+  ,SUBMENU(selMenu)
+  ,SUBMENU(chooseMenu)
+  ,OP("Save",saveTarget,enterEvent)
+  ,EXIT("<Back")
+);
+
+//handling the user menu selection
+//
+result targetEvent(eventMask e,navNode& nav) {
+  _trace(MENU_DEBUG_OUT<<"copy data to temp.\n");
+  target=myTargets[nav.sel];
+  //you can store nav.sel for future reference
+  return proceed;
+}
+
+struct TargetMenu:UserMenu{
+  using UserMenu::UserMenu;
+
+  // override sz() function to have variable/custom size
+  // inline idx_t sz() const override {return 0;}
+
+  //customizing the print of user menu
+  Used printItem(menuOut& out, int idx,int len) override {
+    return len?out.printText(myTargets[idx].name,len):0;
+  }
+};
+
+//build the user menu object, optinally giving a sub menu
+#ifdef MENU_USERAM
+  //for non-AVR devices or when MENU_USERAM is defined at compiler level
+  TargetMenu targetsMenu("Targets",dataSz,targetEdit,targetEvent,enterEvent);
+#else
+  //menu allocation compatible with AVR flash ---------------------------------
+  constMEM char targetsMenuTitle[] MEMMODE="Targets";
+  constMEM menuNodeShadowRaw targetsMenuInfoRaw MEMMODE={
+    (callback)targetEvent,
+    (systemStyles)(_menuData|_canNav),
+    targetsMenuTitle,
+    enterEvent,
+    wrapStyle,
+    dataSz,
+    NULL
+  };
+  constMEM menuNodeShadow& targetsMenuInfo=*(menuNodeShadow*)&targetsMenuInfoRaw;
+  TargetMenu targetsMenu(targetsMenuInfo,targetEdit);
+#endif
+
+MENU(mainMenu,"Main menu",doNothing,noEvent,wrapStyle
+  ,OBJ(targetsMenu)//use in a macro built menu
+  ,EXIT("<Back")
+);
+
+MENU_OUTPUTS(out,MAX_DEPTH
+  ,SERIAL_OUT(Serial)
+  ,NONE//must have 2 items at least
+);
+
+serialIn serial(Serial);
+NAVROOT(nav,mainMenu,MAX_DEPTH,serial,out);
+
+result idle(menuOut &o, idleEvent e) {
+  switch(e) {
+    case idleStart:o.println("suspending menu!");break;
+    case idling:o.println("suspended...");break;
+    case idleEnd:o.println("resuming menu.");
+      nav.reset();
+      break;
+  }
+  return proceed;
+}
+
+void setup() {
+  Serial.begin(115200);
+  while(!Serial);
+  Serial.println("menu 4.x test =================");Serial.flush();
+  nav.timeOut=3000;
+  nav.idleTask=idle;//point a function to be used when menu is suspended
+}
+
+void loop() {
+  nav.poll();
+  delay(100);//simulate a delay when other tasks are done
+}
diff --git a/examples/targetSel/test/README b/examples/targetSel/test/README
new file mode 100644
index 00000000..df5066e6
--- /dev/null
+++ b/examples/targetSel/test/README
@@ -0,0 +1,11 @@
+
+This directory is intended for PIO Unit Testing and project tests.
+
+Unit Testing is a software testing method by which individual units of
+source code, sets of one or more MCU program modules together with associated
+control data, usage procedures, and operating procedures, are tested to
+determine whether they are fit for use. Unit testing finds problems early
+in the development cycle.
+
+More information about PIO Unit Testing:
+- https://docs.platformio.org/page/plus/unit-testing.html
diff --git a/library.properties b/library.properties
index 19e3cc5f..a2cbbf79 100644
--- a/library.properties
+++ b/library.properties
@@ -1,5 +1,5 @@
 name=ArduinoMenu library
-version=4.19.3
+version=4.20.0
 author=Rui Azevedo, ruihfazevedo@gmail.com
 maintainer=neu-rah, ruihfazevedo@gmail.com
 sentence=Generic menu/interactivity system
diff --git a/src/items.h b/src/items.h
index 8f9e1968..3d6cdec1 100644
--- a/src/items.h
+++ b/src/items.h
@@ -52,6 +52,7 @@
         inline styles style() const {return shadow->_style();}
         inline eventMask events() const {return shadow->_events();}
 
+        virtual idx_t sz() const {return 0;}
         inline bool is(systemStyles chk)  const {return (sysStyles()&chk)==chk;}
         inline bool has(systemStyles chk) const {return sysStyles()&chk;}
         inline bool is(styles chk)        const {return (style()&chk)==chk;}
diff --git a/src/macros.h b/src/macros.h
index 831afa0f..34eca2b0 100644
--- a/src/macros.h
+++ b/src/macros.h
@@ -20,9 +20,9 @@
 #endif
 #if defined(USE_PGM) || (defined(pgm_read_ptr_near) && !defined(MENU_USERAM))
   //storing some values into avr flash memory (saving ram space)
-  #ifdef MENU_DEBUG
-    #warning "Using PGM"
-  #endif
+  // #ifdef MENU_DEBUG
+  //   #warning "Using PGM"
+  // #endif
   #define USING_PGM
   #define MEMMODE PROGMEM
   #define constMEM const
@@ -39,9 +39,9 @@
   #define memEnum(addr) (sizeof(int)==1?memByte(addr):memWord(addr))
 #else
   //use ram on non-avr devices or when explicit
-  #ifdef MENU_DEBUG
-    #warning "Using RAM"
-  #endif
+  // #ifdef MENU_DEBUG
+  //   #warning "Using RAM"
+  // #endif
   #define USING_RAM
   #define MEMMODE
   #define constMEM
diff --git a/src/menuBase.h b/src/menuBase.h
index 5798582d..dde85bde 100644
--- a/src/menuBase.h
+++ b/src/menuBase.h
@@ -70,13 +70,13 @@ www.r-site.net
 
     enum result {proceed=0,quit};
     enum systemStyles {
-      _noStyle=0,
-      _menuData=1,
-      _canNav=1<<1,
-      _parentDraw=1<<2,
-      _isVariant=1<<3,
-      _asPad=1<<4,
-      _Exit=1<<5
+      _noStyle=0,//      000000
+      _menuData=1,//     000001
+      _canNav=1<<1,//    000010
+      _parentDraw=1<<2,//000100
+      _isVariant=1<<3,// 001000
+      _asPad=1<<4,//     010000
+      _Exit=1<<5//       100000
     };
     //showTitle and noTitle override the default
     enum styles {
diff --git a/src/menuIO/serialOut.cpp b/src/menuIO/serialOut.cpp
index 04137a23..9e7b7746 100644
--- a/src/menuIO/serialOut.cpp
+++ b/src/menuIO/serialOut.cpp
@@ -3,7 +3,7 @@
 
 namespace Menu {
   #ifdef MENU_DEBUG
-    constexpr idx_t w=16;
+    constexpr idx_t w=20;
   #else
     constexpr idx_t w=40;
   #endif
diff --git a/src/menuIo.cpp b/src/menuIo.cpp
index ec9c0a01..7cc5c3d9 100644
--- a/src/menuIo.cpp
+++ b/src/menuIo.cpp
@@ -44,12 +44,18 @@ menuOut& menuOut::fill(
 
 idx_t menuOut::printRaw(const char* at,idx_t len) {
   trace(MENU_DEBUG_OUT<<"menuOut::printRaw"<<endl);
-  const char* p=at;
+  const char* p=(const char*)at;
   uint8_t ch;
-  for(int n=0;(ch=memByte(at++))&&(len==0||n<len);n++) {
+  for(int n=0;(ch=memByte(p++))&&(len==0||n<len);n++) {
     write(ch);
   }
-  return at-p-1;
+  return p-((const char*)at)-1;
+}
+
+idx_t menuOut::printText(const char* at,idx_t len) {
+  for(int n=0;at[n]&&(len==0||n<len);n++)
+    write(at[n]);
+  return len;
 }
 
 void menuOut::doNav(navCmd cmd,navNode &nav) {
diff --git a/src/menuIo.h b/src/menuIo.h
index 24a46c65..0db2eb01 100644
--- a/src/menuIo.h
+++ b/src/menuIo.h
@@ -75,10 +75,12 @@
         idx_t maxY(idx_t i=0) const;
         idx_t& top(navNode& nav) const;
         // inline void reset() {panelsList.reset();}
+        idx_t printRaw(const char* at,idx_t len);
         inline idx_t printRaw(const __FlashStringHelper* at,idx_t len) {
           return printRaw((const char*)at,len);
         }
-        virtual idx_t printRaw(const char* at,idx_t len);
+        idx_t printText(const __FlashStringHelper* at,idx_t len) {return printRaw(at,len);}
+        idx_t printText(const char* at,idx_t len);
         #if defined(MENU_DEBUG) || defined(MENU_ASYNC)
           virtual menuOut& operator<<(prompt const &p);
           #ifdef ESP8266
diff --git a/src/nav.cpp b/src/nav.cpp
index 91d8c103..743f12f5 100644
--- a/src/nav.cpp
+++ b/src/nav.cpp
@@ -44,18 +44,22 @@ navCmd navNode::doNavigation(navCmd cmd) {
         root->out.doNav(cmd,*this);*/
     case upCmd:
       // trace(MENU_DEBUG_OUT<<"up"<<endl;);
-      nsel++;
-      if (nsel>=sz()) {if(wrap()) nsel=0; else nsel=sz()-1;}
-      // trace(MENU_DEBUG_OUT<<"new sel:"<<nsel<<endl);
+      if(sz()) {
+        nsel++;
+        if (nsel>=sz()) {if(wrap()) nsel=0; else nsel=sz()-1;}
+        // trace(MENU_DEBUG_OUT<<"new sel:"<<nsel<<endl);
+      }
       break;
       /*case scrlUpCmd:
         if (!target->isVariant())
           root->out.doNav(cmd,*this);*/
     case downCmd:
-      // trace(MENU_DEBUG_OUT<<"down"<<endl);
+      trace(MENU_DEBUG_OUT<<"down"<<endl);
       if (nsel||!target->is(_asPad)) {
-        nsel--;
-        if (nsel<0) {if(wrap()) nsel=sz()-1; else nsel=0;}
+        if(sz()) {
+          nsel--;
+          if (nsel<0) {if(wrap()) nsel=sz()-1; else nsel=0;}
+        }
         break;
       }
     case escCmd:
@@ -180,7 +184,7 @@ void navRoot::doNav(navCmd cmd) {
 }
 
 navCmd navRoot::enter() {
-  trace(MENU_DEBUG_OUT<<"navRoot::enter"<<endl);
+  _trace(MENU_DEBUG_OUT<<"navRoot::enter"<<endl);
   if (
     selected().enabled
     &&selected().sysHandler(activateEvent,node(),selected())==proceed
diff --git a/src/plugin/userMenu.h b/src/plugin/userMenu.h
new file mode 100644
index 00000000..40c91015
--- /dev/null
+++ b/src/plugin/userMenu.h
@@ -0,0 +1,62 @@
+/* -*- C++ -*- */
+/********************
+May 2020 Rui Azevedo - ruihfazevedo(@rrob@)gmail.com
+
+www.r-site.net
+
+user print menu with optional submenu
+***/
+
+#include "../menuDefs.h"
+
+namespace Menu {
+
+  // menu with no defined data source, user has to provide a printItem method based on index
+  // menu has static size but user can oiverride sz() function, some info might be placed on flash
+  class UserMenu:public menuNode {
+  public:
+    menu* subMenu=NULL;
+    UserMenu(constMEM menuNodeShadow& shadow):menuNode(shadow) {}
+    UserMenu(constMEM menuNodeShadow& shadow,menu& subMenu):menuNode(shadow),subMenu(&subMenu) {}
+    UserMenu(constText* text,idx_t size,menu& subMenu,action a=noAction,eventMask e=noEvent,styles style=wrapStyle)
+      :menuNode(text,size,NULL,a,e,style,(systemStyles)(_menuData|_canNav)),subMenu(&subMenu) {}
+
+    prompt& operator[](idx_t i) const override {return *(prompt*)this;}
+    virtual Used printItem(menuOut& out, int idx,int len)=0;
+    Used printTo(navRoot &root,bool sel,menuOut& out, idx_t idx,idx_t len,idx_t p) override {
+      if(root.navFocus!=this) return menuNode::printTo(root,sel,out,idx,len,p);
+      return idx<0?
+        menuNode::printTo(root,sel,out,idx,len,p)://print the title
+        printItem(out,idx,len);
+    }
+    void doNav(navNode& nav,navCmd cmd) {
+      if(nav.root->navFocus==this&&cmd.cmd==enterCmd) {
+        _trace(MENU_DEBUG_OUT<<"no sub levels! submenu:"<<(subMenu?"yes":"no")<<" level:"<<nav.root->level<<"\n");
+        //just send the event, but do not open (as this menu is representing the item)
+        // nav.root->path[nav.root->level-1].event(enterEvent);
+        // nav.event(enterEvent);
+        // if(enterEvent&&) operator()(enterEvent, nav, *this);
+        nav.event(enterEvent);
+        if(subMenu) {
+          assert(nav.root->level<nav.root->maxDepth);
+          nav.root->active().dirty=true;
+          nav.root->level++;
+          nav.root->navFocus=nav.root->node().target=subMenu;
+          nav.root->node().sel=0;
+        }
+      } else menuNode::doNav(nav,cmd);
+    }
+  };
+
+  //user menu to use std containers or other structure that provide a size() function
+  //not tested yes, please provide feedback
+  template<typename T>
+  class StdMenu:UserMenu {
+    T& src;
+    StdMenu(constText* text,T& src,action a=noAction,eventMask e=noEvent,styles style=wrapStyle)
+      :menuNode(text,0,NULL,a,e),src(src) {}
+    StdMenu(constText* text,T& src,menu& subMenu,action a=noAction,eventMask e=noEvent,styles style=wrapStyle)
+      :menuNode(text,0,NULL,subMenu,a,e),src(src) {}
+    idx_t sz() const override {return src.size();}
+  };
+};