diff --git a/main.cpp b/main.cpp
index 875898d..6aa65c3 100644
--- a/main.cpp
+++ b/main.cpp
@@ -74,10 +74,12 @@ namespace actions
 
 int main(int argc, char *argv[])
 {
-    const uint32_t clock = 3500000; // 3546900;
+    //const uint32_t clock = 3500000;
+    const uint32_t clock = 3546900;
     const uint32_t update_freq = clock / 10;
 
-    new zx_48mem(); // zx_128mem();
+    //new zx_48mem();
+    new zx_128mem();
 
     z80dis::loadSymbols();
     z80::reset();
@@ -85,8 +87,8 @@ 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_128K);
+    //zxscreen::init(SCREEN_MODE_48K);
 
     ui::menu::init();
     ui::menu::setexitcallback(actions::exitMenu);
@@ -118,7 +120,7 @@ int main(int argc, char *argv[])
     zx_tape::load("fernandomartin.tap");
 
     if (argc==3) { z80debug::loadngo(argv[1], argv[2]); }
-    //z80debug::stop();
+    z80debug::stop();
 
     bool should_exit = false;
     SDL_Event e;
diff --git a/zx_128mem.cpp b/zx_128mem.cpp
index 91ea105..561b5e0 100644
--- a/zx_128mem.cpp
+++ b/zx_128mem.cpp
@@ -22,8 +22,8 @@ zx_128mem::zx_128mem()
 
 void zx_128mem::port_out(int port, int val)
 {
-    const bool shadow = config & ZX_128MEM_SCREEN;
     if (config & ZX_128MEM_DISPAG) return;
+    const bool shadow = config & ZX_128MEM_SCREEN;
     config = val;
     if (config & ZX_128MEM_SCREEN) {
         if (!shadow) zxscreen::setBaseAddresses(0x4000*7, 0x1800+0x4000*7);
@@ -40,7 +40,7 @@ uint8_t zx_128mem::readMem(uint16_t address)
     switch (bank)
     {
         case 0:
-            return rom[disp | ((config & ZX_128MEM_ROM)<<4)];
+            return rom[disp | ((config & ZX_128MEM_ROM)<<10)];
             break;
         case 1:
             return memory[disp | 0x14000];
@@ -52,6 +52,7 @@ uint8_t zx_128mem::readMem(uint16_t address)
             return memory[disp | (0x4000 * (config&ZX_128MEM_PAGE))];
             break;
     }
+    return 0;
 }
 
 void zx_128mem::writeMem(uint16_t address, uint8_t value)
@@ -88,7 +89,7 @@ uint8_t zx_128mem::getTag(uint16_t address)
     switch (bank)
     {
         case 0:
-            return romtags[disp | ((config & ZX_128MEM_ROM)<<4)];
+            return romtags[disp | ((config & ZX_128MEM_ROM)<<10)];
             break;
         case 1:
             return tags[disp | 0x14000];
@@ -111,7 +112,7 @@ void zx_128mem::setTag(uint16_t address, uint8_t value)
     switch (bank)
     {
         case 0:
-            romtags[disp | ((config & ZX_128MEM_ROM)<<4)] = value;
+            romtags[disp | ((config & ZX_128MEM_ROM)<<10)] = value;
             break;
         case 1:
             tags[disp | 0x14000] = value;
@@ -135,6 +136,7 @@ void zx_128mem::reset()
     for (int i=0; i<131072; ++i) tags[i] = MEMTAG_NONE;
 
     z80::connect_port(0x7ffd, nullptr, zx_128_port_out);
+    z80::connect_port(0xfd, nullptr, zx_128_port_out);
 }
 
 void zx_128mem::saveState(FILE *f)