Tweaks to MOSCIA

src/MOSCIA.js

 const BCD = require('utils/bcd.js');
 
 
+function ChangeICBit(cia, v, pos){
+  let mask = ~(1 << pos);
+  v = ((v === true || v === 1) ? 1 : 0) << pos;
+  cia.__IC = (cia.__IC & mask) | v;
+}
+
+
+function TODTick(cia){
+  cia.__TODTick += 1;
+  if (cia.__TODTick === 6){
+    cia.__TODTick = cia.__CTA & 0x01;
+    if (cia.__10ths == 0x09){
+      cia.__10ths = 0;
+      if (cia.__sec == 0x59){
+        cia.__sec = 0;
+        if (cia.__min == 0x59){
+          cia.__min = 0;
+          if (cia.__hour == 0x11 || cia.__hour == 0x91){
+            cia.__hour = (cia.__hour == 0x91) ? 0x00 : 0x10;
+          } else {
+            let pm = cia.__hour & 0x80;
+            cia.__hour = BCD.add(cia.__hour & 0x7F, 0x01, 2) | pm;
+          }
+        } else {cia.__min = BCD.add(cia.__min, 0x01, 2);}
+      } else {cia.__sec = BCD.add(cia.__sec, 0x01, 2);}
+    } else {cia.__10ths = BCD.add(cia.__10ths, 0x01, 2);}
+  }
+
+  if (cia.__10ths == cia.__AL10ths && cia.__sec == cia.__ALsec && cia.__min == cia.__ALmin && cia.__hour == cia.__ALhour){
+    ChangeICBit(cia, 1, 2);
+  }
+}
+
+
 class MOSCIA{
   constructor(){
     this.__regsel = 0;
 
     this.__CTA = 0;
     this.__CTB = 0;
+    this.__IC = 0;
 
     this.__timerA = 0;
     this.__timerALatch = 0;
     this.__timerB = 0;
     this.__timerBLatch = 0;
 
+    // Time Of Day
     this.__TODLatch = 0;
     this.__TODTick = 0;
     this.__10ths = 0;
     this.__sec = 0;
     this.__min = 0;
-    this.__hours = 0;
+    this.__hour = 0;
+
+    // TOD Alarm
+    this.__AL10ths = 0;
+    this.__ALsec = 0;
+    this.__ALmin = 0;
+    this.__ALhour = 0;
   }
 
   get RS(){return this.__regsel;}
   get TOD(){return 0;}
   set TOD(b){
     if (b <= 0 || this.__TODLatch > 0){return;}
-    this.__TODTick += 1;
-    if (this.__TODTick === 6){
-      this.__TODTick = this.__CTA & 0x01;
-      if (this.__10ths == 0x09){
-        this.__10ths = 0;
-        if (this.__sec == 0x59){
-          this.__sec = 0;
-          if (this.__min == 0x59){
-            this.__min = 0;
-            if (this.__hour == 0x11 || this.__hour == 0x91){
-              this.__hour = (this.__hour == 0x91) ? 0x00 : 0x10;
-            } else {
-              let pm = this.__hour & 0x80;
-              this.__hour = BCD.add(this.__hour & 0x7F, 0x01, 2) | pm;
-            }
-          } else {this.__min = BCD.add(this.__min, 0x01, 2);}
-        } else {this.__sec = BCD.add(this.__sec, 0x01, 2);}
-      } else {this.__10ths = BCD.add(this.__10ths, 0x01, 2);}
-    }
+    TODTick(this); 
   }
 }