MOS CIA can now be reset. Serial communication implemented.

src/MOSCIA.js

 class MOSCIA{
   constructor(){
     this.__regsel = 0;
+    this.__RW = 0;
 
     this.__CNT = 0;
+    
+    this.__SP = 0;
+    this.__SPi = 0;
+    this.__SData = 0;
 
     this.__PDA = 0;
     this.__PDB = 0;
     this.__ICMask = 0;
 
     this.__timerA = 0;
-    this.__timerALatch = 0;
+    this.__timerALatch = 1;
     this.__timerB = 0;
-    this.__timerBLatch = 0;
+    this.__timerBLatch = 1;
 
     // Time Of Day
     this.__TODLatch = 0;
   get RS(){return this.__regsel;}
   set RS(rs){this.__regsel = rs & 0x0F;}
 
+  get RW(){return this.__RW;}
+  set RW(rw){this.__RW = (rw === true || rw === 1) ? 1 : 0;}
+
   get DATA(){
     let val = 0;
     switch(this.__regsel){
         TODLatch(this);
         val = this.__LTOD[3]; break;
       case 0x0C: // Serial Data
-        break;
+        val = this.__SData; break;
       case 0x0D: // Interrupt Control
         let v = this.__IC;
         this.__IC = 0;
   }
 
   set DATA(d){
+    if (this.__RW === 1){return;}
     switch(this.__regsel){
       case 0x00: // Peripheral Data A
         break;
       if (BITM.isOn(this.__CTA, 0) && BITM.isOn(this.__CTA, 5))
         TimerATick(this);
 
-      if (BITM.isOn(this.__CTB, 0){
+      if (BITM.isOn(this.__CTB, 0)){
         let cs = (this.__CTB & 0x60) >> 5;
         if (cs === 1)
           TimerBTick(this);
       }
+
+      if (BITM.isOn(this.__CTA, 6)){
+        if (this.__SPi > 0){
+          this.__SP = BITM.val(this.__SData, 7);
+          this.__SData = this.__SData << 1;
+          this.__SPi -= 1;
+          if (this.__SPi === 0)
+            BITM.set(this.__IC, 3);
+        }
+      } else {
+        if (this.__SPi < 7){
+          this.__SData = (this.__SData << 1) | this.__SP;
+          this.__SPi += 1;
+          if (this.__SPi === 7)
+            BITM.set(this.__IC, 3);
+        }
+      }
     }
   }
 
-  get SP(){return 0;}
-  set SP(b){}
+  get SP(){return this.__SP;}
+  set SP(sp){
+    this.__SP = (sp === true || sp === 1) ? 1 : 0;
+  }
 
   get TOD(){return 0;}
   set TOD(b){
   get phi2(){return 0;}
   set phi2(p){
     if (p >= 1){
-      if (BITM.isOn(this.__CTA, 0) && !BITM.isOn(this.__CTA, 5)){
-        TimerATick(this);
+      if (BITM.isOn(this.__CTA, 0)){
+        if (BITM.isOn(cia.__CTA, 1) && !BITM.isOn(cia.__CTA, 2))
+          cia.__PDB = BITM.clear(cia.__PDB, 6);
+
+        if (!BITM.isOn(this.__CTA, 5))
+          TimerATick(this);
       }
       if (BITM.isOn(this.__CTB, 0)){
+        if (BITM.isOn(cia.__CTB, 1) && !BITM.isOn(cia.__CTB, 2))
+          cia.__PDB = BITM.clear(cia.__PDB, 7);
+
         let cs = (this.__CTB & 0x60) >> 5;
         if (cs === 0)
           TimerBTick(this);
       }
     }
   }
+
+
+  reset(){
+    this.__CNT = 0;
+
+    this.__PDA = 0;
+    this.__PDB = 0;
+    this.__DDA = 0;
+    this.__DDB = 0;
+
+    this.__CTA = 0;
+    this.__CTB = 0;
+
+    this.__IC = 0;
+    this.__ICMask = 0;
+
+    this.__timerA = 0;
+    this.__timerALatch = 1;
+    this.__timerB = 0;
+    this.__timerBLatch = 1;
+
+    // Time Of Day
+    this.__TODLatch = 0;
+    this.__TODTick = 0;
+    this.__TOD = [0,0,0,0];
+    this.__LTOD = [0,0,0,0];
+    this.__ALTOD = [0,0,0,0];
+  }
 }