Added pages property to memory. Bringing MMC more inline with IMem interface.

src/memory/imem.js

 class IMem{
   constructor(){}
 
+  get pages(){return 0;}
   get size(){return 0;}
   get writable(){return false;}
 

src/memory/memory.js

     this.__rlisteners = new Listener();
   }
 
+  get pages(){return this.__map.length / 256;}
   get size(){return this.__map.length;}
 
   get address(){return this.__addr;}
     this.__wlisteners = new Listener();
   }
 
+  get pages(){return this.__map.length/256;}
   get size(){return this.__map.length;}
   get writable(){return true;}
 
     this.__wlisteners = new Listener();
   }
 
+  get pages(){return this.__size/256;}
   get size(){return this.__size;}
+  get registers(){return this.__map.length;}
   get writable(){return true;}
 
   get address(){return this.__addr;}

src/memory/mmc.js

     this.__sidx = 0;
   }
 
+  get pages(){
+    return this.__switches.reduce((acc, s)=>{
+      return acc + s.mem.pages;
+    }, 0);
+  }
+
   get size(){
     return this.__switches.reduce((acc, s)=>{
-      acc += s.mem.size;
+      return acc + s.mem.size;
     }, 0);
   }
 
+  get writable(){
+    let iw = false;
+    for (let i=0; i < this.__switches.length; i++){
+      if (this.__switches[i].mem.writable){
+        iw = true; break;
+      }
+    }
+    return iw;
+  }
+
   get switches(){return this.__switches.length;}
 
   get address(){return this.__addr;}
     }
   }
 
+  load(addr, data){
+    if (addr < 0 || addr > this.size)
+      throw new RangeError("Memory address out of range.");
+    let offset = 0;
+    for (let i = 0; i < this.__switches.length; i++){
+      let mem = this.__switches[i].mem;
+      let od = data;
+      if (addr >= offset && addr < offset + mem.size){
+        if ((addr - offset) + d.length >= mem.size)
+          od = data.slice(0, mem.size);
+        mem.load(addr - offset, od);
+      }
+      data = data.slice(mem.size);
+      offset += mem.size;
+      if (d.length > 0)
+        addr = offset;
+    }
+    return this;
+  }
+
+  clearPage(paddr){
+    for (let i=0; i < this.__switches.length; i++){
+      let pgs = this.__switches[i].mem.pages;
+      if (paddr < pgs){
+        this.__switches[i].mem.clearPage(addr);
+        break;
+      }
+      paddr -= pgs;
+    }
+    return this;
+  }
+
+  clear(){
+    this.__switches.forEach((s)=>{
+      s.clear();
+    });
+    return this;
+  }
+
   connectMemory(mem, addroff){
     addroff = (typeof(addroff) === 'number' && addroff >= 0) ? addroff : -1;
     if (addroff < 0 || addroff === this.size){