diff --git a/main.cpp b/main.cpp
index 6aa65c3..b665c65 100644
--- a/main.cpp
+++ b/main.cpp
@@ -15,6 +15,9 @@
 #include "z80mem.h"
 #include "zx_48mem.h"
 #include "zx_128mem.h"
+#include "z80viewer.h"
+#include "zx_128bankviewer.h"
+#include "zx_128pageviewer.h"
 
 uint8_t memory[65536];
 uint32_t time = 0;
@@ -87,8 +90,16 @@ int main(int argc, char *argv[])
 
     SDL_Init(SDL_INIT_EVERYTHING);
     z80debug::init();
-    zxscreen::init(SCREEN_MODE_128K);
-    //zxscreen::init(SCREEN_MODE_48K);
+    zxscreen::init(SCREEN_MODE_48K);
+    //zxscreen::init(SCREEN_MODE_128K);
+
+    //z80viewer *v = new zx_128bankviewer();
+    //v->show();
+    //z80viewer::registerViewer("128BANK", v);
+
+    //v = new zx_128pageviewer();
+    //v->show();
+    //z80viewer::registerViewer("128PAGE", v);
 
     ui::menu::init();
     ui::menu::setexitcallback(actions::exitMenu);
@@ -121,6 +132,7 @@ int main(int argc, char *argv[])
 
     if (argc==3) { z80debug::loadngo(argv[1], argv[2]); }
     z80debug::stop();
+    z80debug::stop();
 
     bool should_exit = false;
     SDL_Event e;
@@ -156,6 +168,7 @@ int main(int argc, char *argv[])
                     } else {
                         z80debug::show();
                     }
+                    z80viewer::refreshAll();
                 } else if (e.key.keysym.scancode==SDL_SCANCODE_F10) {
                     if (z80debug::debugging()) {
                         z80debug::show();
@@ -165,6 +178,7 @@ int main(int argc, char *argv[])
                         zxscreen::fullrefresh();
                         zxscreen::redraw();
                         z80analyze::refresh();
+                        z80viewer::refreshAll();
                     }
                 } else if (e.key.keysym.scancode==SDL_SCANCODE_F11) {
                     if (z80debug::debugging()) {
@@ -175,6 +189,7 @@ int main(int argc, char *argv[])
                         zxscreen::refresh(dt);
                         zxscreen::redraw();
                         z80analyze::refresh();
+                        z80viewer::refreshAll();
                     }
                 } else if (e.key.keysym.scancode==SDL_SCANCODE_F12) {
                     if (z80debug::debugging()) {
@@ -185,6 +200,7 @@ int main(int argc, char *argv[])
                         zxscreen::refresh(dt);
                         zxscreen::redraw();
                         z80analyze::refresh();
+                        z80viewer::refreshAll();
                     }
                 }
                 result = ui::window::sendEvent(e.key.windowID, &e);
@@ -243,6 +259,7 @@ int main(int argc, char *argv[])
                 t_states -= update_freq;
                 time = SDL_GetTicks();
                 z80analyze::refresh();
+                z80viewer::refreshAll();
             }
             z80analyze::refresh(true);
 
diff --git a/z80.cpp b/z80.cpp
index beb5520..fcd46a2 100644
--- a/z80.cpp
+++ b/z80.cpp
@@ -1,7 +1,7 @@
 #include "z80.h"
 #include "z80debug.h"
 #include "z80mem.h"
-#include "zx_tape.h"
+//#include "zx_tape.h"
 #include <stdio.h>
 
 namespace z80
@@ -15,8 +15,8 @@ namespace z80
     bool options[Z80_NUM_OPTIONS] = { true, false };
     int calls_stacked = 0;
 
-    int (*in_ports[65536])(int);
-    void (*out_ports[65536])(int, int);
+    int (*in_ports[256])(int);
+    void (*out_ports[256])(int, int);
 
     //#define _rM16(a) (uint16_t*)&memory[a]
     //#define rM16(a) *_rM16(a)
@@ -186,10 +186,10 @@ namespace z80
     {
         t+=1;
         reading_m1 = true;
-        if (rPC==0x056c) {
+        /*if (rPC==0x056c) {
             zx_tape::rewind();
             zx_tape::play();
-        }
+        }*/
         return READ_MEM_8();
     }
 
@@ -1008,6 +1008,7 @@ namespace z80
         t+=4;
         if (port == 0x10000) {
             port = rBC;
+            if (rC==0xfe) port = 0xfe;
         }
         if (out_ports[port&0xff]) out_ports[port&0xff](port, val);
     }
@@ -2265,7 +2266,7 @@ namespace z80
         switch (opcode)
         {
             case 0x40: rB = IN();                       break;
-            case 0x41: OUT(rB, rC);                     break;
+            case 0x41: OUT(rB);                     break;
             case 0x42: SBC16(_rHL, rBC);                break;
             case 0x43: WRITE_MEM_16(READ_MEM_16(), rBC);break;
             case 0x44: NEG();                           break;
@@ -2273,42 +2274,42 @@ namespace z80
             case 0x46: IM(0);                           break;
             case 0x47: rI = rA; t++;                    break;
             case 0x48: rC = IN();                       break;
-            case 0x49: OUT(rC, rC);                     break;
+            case 0x49: OUT(rC);                     break;
             case 0x4A: ADC16(_rHL, rBC);                break;
             case 0x4B: rBC = READ_MEM_16(READ_MEM_16());break;
             case 0x4D: RETI();                          break;
             case 0x4F: rR = rA; t++;                    break;
 
             case 0x50: rD = IN();                       break;
-            case 0x51: OUT(rD, rC);                     break;
+            case 0x51: OUT(rD);                     break;
             case 0x52: SBC16(_rHL, rDE);                break;
             case 0x53: WRITE_MEM_16(READ_MEM_16(), rDE);break;
             case 0x56: IM(1);                           break;
             case 0x57: LD_A_I();                        break;
             case 0x58: rE = IN();                       break;
-            case 0x59: OUT(rE, rC);                     break;
+            case 0x59: OUT(rE);                     break;
             case 0x5A: ADC16(_rHL, rDE);                break;
             case 0x5B: rDE = READ_MEM_16(READ_MEM_16());break;
             case 0x5E: IM(2);                           break;
             case 0x5F: LD_A_R();                        break;
 
             case 0x60: rH = IN();                       break;
-            case 0x61: OUT(rH, rC);                     break;
+            case 0x61: OUT(rH);                     break;
             case 0x62: SBC16(_rHL, rHL);                break;
             case 0x63: WRITE_MEM_16(READ_MEM_16(), rHL);break;
             case 0x67: RRD();                           break;
             case 0x68: rL = IN();                       break;
-            case 0x69: OUT(rL, rC);                     break;
+            case 0x69: OUT(rL);                     break;
             case 0x6A: ADC16(_rHL, rHL);                break;
             case 0x6B: rHL = READ_MEM_16(READ_MEM_16());break;
             case 0x6F: RLD();                           break;
 
             case 0x70: IN();                            break;
-            case 0x71: OUT(0, rC);                      break;
+            case 0x71: OUT(0);                      break;
             case 0x72: SBC16(_rHL, rSP);                break;
             case 0x73: WRITE_MEM_16(READ_MEM_16(), rSP);break;
             case 0x78: rA = IN();                       break;
-            case 0x79: OUT(rA, rC);                     break;
+            case 0x79: OUT(rA);                     break;
             case 0x7A: ADC16(_rHL, rSP);                break;
             case 0x7B: rSP = READ_MEM_16(READ_MEM_16());break;
 
diff --git a/z80analyze.cpp b/z80analyze.cpp
index 3a2994a..5ee39ce 100644
--- a/z80analyze.cpp
+++ b/z80analyze.cpp
@@ -84,6 +84,7 @@ namespace z80analyze
             SDL_SetWindowTitle(win, SDL_itoa(address, tmp, 16));
         }
     }
+    
     void refresh(const bool conditional)
     {
         if (!win) return;
diff --git a/z80debug.cpp b/z80debug.cpp
index bef20da..85f6cc2 100644
--- a/z80debug.cpp
+++ b/z80debug.cpp
@@ -801,6 +801,7 @@ namespace z80debug
         } else if (strcmp(cmd, "r")==0 || strcmp(cmd, "reset")==0) {
             z80::reset();
             z80::connect_port(0xfe, zx_ula::port_in, zx_ula::port_out);
+            history::reset();
             z80debug::refresh();
             z80analyze::refresh();
         } else if (strcmp(cmd, "b")==0 || strcmp(cmd, "break")==0) {
@@ -897,6 +898,7 @@ namespace z80debug
             else if (strcmp(cmd, "d")==0) { getcmd(); int value = getnum(cmd); z80::getRegs()[5] = value; }
             else if (strcmp(cmd, "l")==0) { getcmd(); int value = getnum(cmd); z80::getRegs()[6] = value; }
             else if (strcmp(cmd, "h")==0) { getcmd(); int value = getnum(cmd); z80::getRegs()[7] = value; }
+            else if (strcmp(cmd, "pc")==0) { getcmd(); int value = getnum(cmd); z80::getRegs()[24] = value&0xff; z80::getRegs()[25] = (value>>8)&0xff; }
             else { sendToConsoleLog("Syntax error: invalid register"); return; }
         } else if (strcmp(cmd, "g")==0 || strcmp(cmd, "goto")==0) {
             getcmd();
@@ -1149,6 +1151,12 @@ namespace z80debug
 
     namespace history
     {
+        void reset()
+        {
+            buffer[0]=buffer[1]=0;
+            cursor=pos=top=0;
+        }
+
         void store()
         {
             buffer[++top] = z80::getPC();
diff --git a/z80debug.h b/z80debug.h
index d89d13b..a4c86b1 100644
--- a/z80debug.h
+++ b/z80debug.h
@@ -44,6 +44,7 @@ namespace z80debug
     void search(const char *seq=nullptr);
     namespace history
     {
+        void reset();
         void store();
         void gototop();
         void goforward();
diff --git a/z80mem.h b/z80mem.h
index b41a19e..aeacdea 100644
--- a/z80mem.h
+++ b/z80mem.h
@@ -36,6 +36,7 @@ class z80mem
         virtual uint32_t getSize() = 0;
 
         virtual uint8_t *rawPtr(uint32_t address) = 0;
+        virtual uint8_t *rawTagPtr(uint32_t address) = 0;
     
     protected:
 
diff --git a/z80viewer.cpp b/z80viewer.cpp
new file mode 100644
index 0000000..31368b6
--- /dev/null
+++ b/z80viewer.cpp
@@ -0,0 +1,33 @@
+#include "z80viewer.h"
+#include "ui.h"
+#include "ui_window.h"
+
+std::vector<viewer_t> z80viewer::viewers;
+
+void z80viewer::registerViewer(const char *name, z80viewer *viewer)
+{
+    viewer_t v;
+    strcpy(v.name, name);
+    v.viewer = viewer;
+    viewers.push_back( v );
+}
+
+z80viewer *z80viewer::getViewer(const char *name)
+{
+    for (auto v : viewers)
+    {
+        if (strcmp(name, v.name)==0) return v.viewer;
+    }
+    return nullptr;
+}
+
+void z80viewer::refreshAll()
+{
+    for (auto v : viewers) v.viewer->refresh();
+}
+
+bool z80viewer::handleEvents(SDL_Event *e)
+{
+    for (auto v : viewers) v.viewer->handleEvent(e);
+    return true;
+}
\ No newline at end of file
diff --git a/z80viewer.h b/z80viewer.h
new file mode 100644
index 0000000..f73e572
--- /dev/null
+++ b/z80viewer.h
@@ -0,0 +1,34 @@
+#pragma once
+#include <SDL2/SDL.h>
+#include <vector>
+
+class z80viewer;
+
+struct viewer_t
+{
+    char        name[12];
+    z80viewer  *viewer;
+};
+
+class z80viewer
+{
+    public:
+        virtual void show() = 0;
+        virtual void refresh() = 0;
+        virtual void hide() = 0;
+        virtual void focus() = 0;
+        virtual bool handleEvent(SDL_Event *e) = 0;
+
+        static void registerViewer(const char *name, z80viewer *viewer);
+        static z80viewer *getViewer(const char *name);
+        static void refreshAll();
+        static bool handleEvents(SDL_Event *e);
+        
+    protected:
+        SDL_Window *win = nullptr;
+        SDL_Renderer *ren = nullptr;
+        SDL_Texture *tex = nullptr;
+        SDL_Texture *uitex = nullptr;
+
+        static std::vector<viewer_t> viewers;
+};
diff --git a/zx_128bankviewer.cpp b/zx_128bankviewer.cpp
new file mode 100644
index 0000000..ab5dae6
--- /dev/null
+++ b/zx_128bankviewer.cpp
@@ -0,0 +1,60 @@
+#include "zx_128bankviewer.h"
+#include "z80.h"
+#include "z80mem.h"
+
+void zx_128bankviewer::show()
+{
+    if (!win)
+    {
+        win = SDL_CreateWindow("Z80 Analyzer", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 128, 512, SDL_WINDOW_SHOWN);
+        ren = SDL_CreateRenderer(win, -1, 0);
+        tex = SDL_CreateTexture(ren, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STREAMING, 128, 512);
+
+        //ui::window::registerWindow(SDL_GetWindowID(win), handleEvent);
+    }
+    refresh();
+}
+
+
+void zx_128bankviewer::refresh()
+{
+        if (!win) return;
+
+        Uint32 *pixels;
+        int pitch;
+        SDL_LockTexture(tex, NULL, (void**)&pixels, &pitch);
+        for (int i=0; i<65536; ++i)
+        {
+            //uint8_t tag = z80::getMemTag(i);
+            //pixels[i] = tag==MEMTAG_NONE ? 0x808080 : tag==MEMTAG_DATA ? 0x0000FF : tag==MEMTAG_MIXED ? 0xFF00FF : 0x00FF00;
+            uint32_t none_color = i<0x4000 ? 0x101010 : i<0x5800 ? 0x202020 : i<0x5b00 ? 0x404040 : 0x808080;
+            uint8_t tag = z80mem::get()->getTag(i);
+            pixels[i] = !(tag & MEMTAG_TOUCHED) ? none_color : (tag & MEMTAG_TINST) ? 0x00FF00 : (tag & MEMTAG_TREPEAT) ? 0xFF0000 : 0x0000FF;
+        }
+        pixels[z80::getPC()] = 0xFFFFFF;
+
+        SDL_UnlockTexture(tex);
+        SDL_RenderCopy(ren, tex, NULL, NULL);
+        SDL_RenderPresent(ren);
+}
+
+void zx_128bankviewer::hide()
+{
+    //ui::window::unregisterWindow(SDL_GetWindowID(win));
+    SDL_DestroyTexture(tex); tex = nullptr;
+    SDL_DestroyRenderer(ren); ren = nullptr;
+    SDL_DestroyWindow(win); win = nullptr;
+}
+
+void zx_128bankviewer::focus()
+{
+    if (win) {
+        SDL_RaiseWindow(win);
+        refresh();
+    }
+}
+
+bool zx_128bankviewer::handleEvent(SDL_Event *e)
+{
+    return true;
+}
diff --git a/zx_128bankviewer.h b/zx_128bankviewer.h
new file mode 100644
index 0000000..7641246
--- /dev/null
+++ b/zx_128bankviewer.h
@@ -0,0 +1,12 @@
+#pragma once
+#include "z80viewer.h"
+
+class zx_128bankviewer : public z80viewer
+{
+    public:
+        void show();
+        void refresh();
+        void hide();
+        void focus();
+        bool handleEvent(SDL_Event *e);
+};
diff --git a/zx_128mem.cpp b/zx_128mem.cpp
index 561b5e0..75571de 100644
--- a/zx_128mem.cpp
+++ b/zx_128mem.cpp
@@ -6,7 +6,7 @@
 #include <stdio.h>
 
 #define ZX_128MEM_PAGE      0x07
-#define ZX_128MEM_SCREEN    0x04
+#define ZX_128MEM_SCREEN    0x08
 #define ZX_128MEM_ROM       0x10
 #define ZX_128MEM_DISPAG    0x20
 
@@ -157,4 +157,9 @@ uint32_t zx_128mem::getSize()
 uint8_t *zx_128mem::rawPtr(uint32_t address)
 {
     return &memory[address];
-}
\ No newline at end of file
+}
+
+uint8_t *zx_128mem::rawTagPtr(uint32_t address)
+{
+    return &tags[address];
+}
diff --git a/zx_128mem.h b/zx_128mem.h
index 5b3b756..af467ac 100644
--- a/zx_128mem.h
+++ b/zx_128mem.h
@@ -26,6 +26,7 @@ class zx_128mem : public z80mem
         uint32_t getSize();
 
         uint8_t *rawPtr(uint32_t address);
+        uint8_t *rawTagPtr(uint32_t address);
 
     protected:
 
diff --git a/zx_128pageviewer.cpp b/zx_128pageviewer.cpp
new file mode 100644
index 0000000..910079e
--- /dev/null
+++ b/zx_128pageviewer.cpp
@@ -0,0 +1,61 @@
+#include "zx_128pageviewer.h"
+#include "z80.h"
+#include "z80mem.h"
+
+void zx_128pageviewer::show()
+{
+    if (!win)
+    {
+        win = SDL_CreateWindow("ZX128 Page Viewer", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 1024, 128, SDL_WINDOW_SHOWN);
+        ren = SDL_CreateRenderer(win, -1, 0);
+        tex = SDL_CreateTexture(ren, SDL_PIXELFORMAT_ARGB8888, SDL_TEXTUREACCESS_STREAMING, 1024, 128);
+
+        //ui::window::registerWindow(SDL_GetWindowID(win), handleEvent);
+    }
+    refresh();
+}
+
+
+void zx_128pageviewer::refresh()
+{
+        if (!win) return;
+
+        Uint32 *pixels;
+        int pitch;
+        const uint8_t *tags = z80mem::get()->rawTagPtr(0);
+        SDL_LockTexture(tex, NULL, (void**)&pixels, &pitch);
+        for (int i=0; i<131072; ++i)
+        {
+            const int x = (i&0x7f) + (((i>>14)&0x07)*128);
+            const int y = (i>>7)&0x7f;
+            uint32_t none_color = 0x808080; //i<0x4000 ? 0x101010 : i<0x5800 ? 0x202020 : i<0x5b00 ? 0x404040 : 0x808080;
+            uint8_t tag = tags[i];
+            pixels[x+y*1024] = !(tag & MEMTAG_TOUCHED) ? none_color : (tag & MEMTAG_TINST) ? 0x00FF00 : (tag & MEMTAG_TREPEAT) ? 0xFF0000 : 0x0000FF;
+        }
+        //pixels[z80::getPC()] = 0xFFFFFF;
+
+        SDL_UnlockTexture(tex);
+        SDL_RenderCopy(ren, tex, NULL, NULL);
+        SDL_RenderPresent(ren);
+}
+
+void zx_128pageviewer::hide()
+{
+    //ui::window::unregisterWindow(SDL_GetWindowID(win));
+    SDL_DestroyTexture(tex); tex = nullptr;
+    SDL_DestroyRenderer(ren); ren = nullptr;
+    SDL_DestroyWindow(win); win = nullptr;
+}
+
+void zx_128pageviewer::focus()
+{
+    if (win) {
+        SDL_RaiseWindow(win);
+        refresh();
+    }
+}
+
+bool zx_128pageviewer::handleEvent(SDL_Event *e)
+{
+    return true;
+}
diff --git a/zx_128pageviewer.h b/zx_128pageviewer.h
new file mode 100644
index 0000000..df570c8
--- /dev/null
+++ b/zx_128pageviewer.h
@@ -0,0 +1,13 @@
+#pragma once
+#include "z80viewer.h"
+
+class zx_128pageviewer : public z80viewer
+{
+    public:
+        void show();
+        void refresh();
+        void hide();
+        void focus();
+
+        bool handleEvent(SDL_Event *e);
+};
diff --git a/zx_48mem.cpp b/zx_48mem.cpp
index fa1e612..1a9c6b3 100644
--- a/zx_48mem.cpp
+++ b/zx_48mem.cpp
@@ -62,4 +62,9 @@ uint32_t zx_48mem::getSize()
 uint8_t *zx_48mem::rawPtr(uint32_t address)
 {
     return &memory[address];
+}
+
+uint8_t *zx_48mem::rawTagPtr(uint32_t address)
+{
+    return &tags[address];
 }
\ No newline at end of file
diff --git a/zx_48mem.h b/zx_48mem.h
index 5309b20..4f2f6d1 100644
--- a/zx_48mem.h
+++ b/zx_48mem.h
@@ -22,6 +22,7 @@ class zx_48mem : public z80mem
         uint32_t getSize();
 
         uint8_t *rawPtr(uint32_t address);
+        uint8_t *rawTagPtr(uint32_t address);
 
     protected:
 
diff --git a/zx_ula.cpp b/zx_ula.cpp
index b41c3cd..f862690 100644
--- a/zx_ula.cpp
+++ b/zx_ula.cpp
@@ -293,11 +293,11 @@ namespace zx_ula
         if (t_sound>=317) {
             t_sound-=317;
             samples_generated++;
-            if (samples_t >=z80::getClock()) {
+            /*if (samples_t >=z80::getClock()) {
                 //printf("%i\n", samples_generated);
                 samples_generated=0;
                 samples_t = 0;
-            }
+            }*/
             /*if (SDL_GetTicks()>=samples_time+1000) {
                 printf("%i\n", samples_generated);
                 samples_generated=0;