Implemented INC/DEC opcodes

modules/pdp11/lib/cpuops.js

@@ -38,22 +38,22 @@ if (NODE) {
 }
 
 /**
- * fnADD(dst, src)
+ * fnADD(src, dst)
  *
  * @this {CPUStatePDP11}
  * @param {number} src
  * @param {number} dst
- * @return {number} (src + dst)
+ * @return {number} (dst + src)
  */
 PDP11.fnADD = function(src, dst)
 {
-    var result = src + dst;
+    var result = dst + src;
     this.updateAddFlags(result, src, dst);
     return result & 0xffff;
 };
 
 /**
- * fnBIC(dst, src)
+ * fnBIC(src, dst)
  *
  * @this {CPUStatePDP11}
  * @param {number} src
@@ -62,13 +62,13 @@ PDP11.fnADD = function(src, dst)
  */
 PDP11.fnBIC = function(src, dst)
 {
-    var result = ~src & dst;
+    var result = dst & ~src;
     this.updateNZFlags(result);
     return result;
 };
 
 /**
- * fnBICB(dst, src)
+ * fnBICB(src, dst)
  *
  * @this {CPUStatePDP11}
  * @param {number} src
@@ -77,43 +77,73 @@ PDP11.fnBIC = function(src, dst)
  */
 PDP11.fnBICB = function(src, dst)
 {
-    var result = ~src & dst;
+    var result = dst & ~src;
     this.updateNZFlags(result << 8);
     return result;
 };
 
 /**
- * fnBIS(dst, src)
+ * fnBIS(src, dst)
  *
  * @this {CPUStatePDP11}
  * @param {number} src
  * @param {number} dst
- * @return {number} (src | dst)
+ * @return {number} (dst | src)
  */
 PDP11.fnBIS = function(src, dst)
 {
-    var result = src | dst;
+    var result = dst | src;
     this.updateNZFlags(result);
     return result;
 };
 
 /**
- * fnBISB(dst, src)
+ * fnBISB(src, dst)
  *
  * @this {CPUStatePDP11}
  * @param {number} src
  * @param {number} dst
- * @return {number} (src | dst)
+ * @return {number} (dst | src)
  */
 PDP11.fnBISB = function(src, dst)
 {
-    var result = src | dst;
+    var result = dst | src;
     this.updateNZFlags(result << 8);
     return result;
 };
 
 /**
- * fnSUB(dst, src)
+ * fnDEC(src, dst)
+ *
+ * @this {CPUStatePDP11}
+ * @param {number} src (ie, 1)
+ * @param {number} dst
+ * @return {number} (dst - src)
+ */
+PDP11.fnDEC = function(src, dst)
+{
+    var result = dst - src;
+    this.updateDecFlags(result, src, dst);
+    return result & 0xffff;
+};
+
+/**
+ * fnINC(src, dst)
+ *
+ * @this {CPUStatePDP11}
+ * @param {number} src (ie, 1)
+ * @param {number} dst
+ * @return {number} (dst + src)
+ */
+PDP11.fnINC = function(src, dst)
+{
+    var result = dst + src;
+    this.updateIncFlags(result, src, dst);
+    return result & 0xffff;
+};
+
+/**
+ * fnSUB(src, dst)
  *
  * @this {CPUStatePDP11}
  * @param {number} src
@@ -689,10 +719,7 @@ PDP11.opCOMB = function(opCode)
  */
 PDP11.opDEC = function(opCode)
 {
-    /*
+    this.updateWordByMode(opCode, 1, PDP11.fnDEC);
-     * TODO: Implement
-     */
-    this.regOp = -1;
     this.nStepCycles -= 1;
 };
 
@@ -764,10 +791,7 @@ PDP11.opHALT = function(opCode)
  */
 PDP11.opINC = function(opCode)
 {
-    /*
+    this.updateWordByMode(opCode, 1, PDP11.fnINC);
-     * TODO: Implement
-     */
-    this.regOp = -1;
     this.nStepCycles -= 1;
 };
 

modules/pdp11/lib/cpustate.js

@@ -512,7 +512,7 @@ CPUStatePDP11.prototype.getPC = function()
  */
 CPUStatePDP11.prototype.setPC = function(addr)
 {
-    this.regsGen[7] = addr;
+    this.regsGen[7] = addr & 0xffff;
 };
 
 /**
@@ -526,6 +526,17 @@ CPUStatePDP11.prototype.getSP = function()
     return this.regsGen[6];
 };
 
+/**
+ * setSP()
+ *
+ * @this {CPUStatePDP11}
+ * @param {number} addr
+ */
+CPUStatePDP11.prototype.setSP = function(addr)
+{
+    this.regsGen[6] = addr & 0xffff;
+};
+
 /**
  * requestHALT()
  *
@@ -702,6 +713,8 @@ CPUStatePDP11.prototype.setPSW = function(newPSW)
 /**
  * updateNZCFlags(result)
  *
+ * NOTE: The V flag is simply zeroed, it is not "updated" based on the result.
+ *
  * @this {CPUStatePDP11}
  * @param {number} result
  */
@@ -716,6 +729,8 @@ CPUStatePDP11.prototype.updateNZCFlags = function(result)
 /**
  * updateNZFlags(result)
  *
+ * NOTE: The V flag is simply zeroed, it is not "updated" based on the result.
+ *
  * @this {CPUStatePDP11}
  * @param {number} result
  */
@@ -743,6 +758,44 @@ CPUStatePDP11.prototype.updateAddFlags = function(result, src, dst)
     }
 };
 
+/**
+ * updateIncFlags(result, src, dst)
+ *
+ * NOTE: We could have used updateAddFlags() if not for the fact that the C flag must be preserved.
+ *
+ * @this {CPUStatePDP11}
+ * @param {number} result (dst + src)
+ * @param {number} src (ie, 1)
+ * @param {number} dst
+ */
+CPUStatePDP11.prototype.updateIncFlags = function(result, src, dst)
+{
+    if (!(this.opFlags & PDP11.OPFLAG.SKIP_FLAGS)) {
+        this.flagN = this.flagZ = result;
+        // Because src is always 1 (with a zero sign bit), it can be optimized out of this calculation
+        this.flagV = (/* src ^ */ result) & (dst ^ result);
+    }
+};
+
+/**
+ * updateDecFlags(result, src, dst)
+ *
+ * NOTE: We could have used updateSubFlags() if not for the fact that the C flag must be preserved.
+ *
+ * @this {CPUStatePDP11}
+ * @param {number} result (dst - src)
+ * @param {number} src (ie, 1)
+ * @param {number} dst
+ */
+CPUStatePDP11.prototype.updateDecFlags = function(result, src, dst)
+{
+    if (!(this.opFlags & PDP11.OPFLAG.SKIP_FLAGS)) {
+        this.flagN = this.flagZ = result;
+        // Because src is always 1 (with a zero sign bit), it can be optimized out of this calculation
+        this.flagV = (/* src ^ */ dst) & (dst ^ result);
+    }
+};
+
 /**
  * updateSubFlags(result, src, dst)
  *

modules/pdp11/lib/debugger.js

@@ -3140,38 +3140,44 @@ if (DEBUGGER) {
                 return;
             }
 
-            var fValid = false;
             var w = this.parseExpression(sValue);
+            if (w === undefined) return;
 
-            if (w !== undefined) {
+            var sRegMatch = sReg.toUpperCase();
-                fValid = true;
+            switch (sRegMatch) {
-                var sRegMatch = sReg.toUpperCase();
+            case "SP":
-                switch (sRegMatch) {
+            case "R6":
-                case "PC":
+                cpu.setSP(w);
-                    cpu.setPC(w);
+                break;
-                    this.dbgAddrNextCode = this.newAddr(cpu.getPC());
+            case "PC":
-                    break;
+            case "R7":
-                case "NF":
+                cpu.setPC(w);
-                    if (w) cpu.setNF(); else cpu.clearNF();
+                this.dbgAddrNextCode = this.newAddr(cpu.getPC());
-                    break;
+                break;
-                case "ZF":
+            case "N":
-                    if (w) cpu.setZF(); else cpu.clearZF();
+                if (w) cpu.setNF(); else cpu.clearNF();
-                    break;
+                break;
-                case "VF":
+            case "Z":
-                    if (w) cpu.setVF(); else cpu.clearVF();
+                if (w) cpu.setZF(); else cpu.clearZF();
-                    break;
+                break;
-                case "CF":
+            case "V":
-                    if (w) cpu.setCF(); else cpu.clearCF();
+                if (w) cpu.setVF(); else cpu.clearVF();
-                    break;
+                break;
-                default:
+            case "C":
-                    this.println("unknown register: " + sReg);
+                if (w) cpu.setCF(); else cpu.clearCF();
-                    return;
+                break;
+            default:
+                if (sRegMatch.charAt(0) == 'R') {
+                    var iReg = +sRegMatch.charAt(1);
+                    if (iReg >= 0 && iReg < 6) {
+                        cpu.regsGen[iReg] = w & 0xffff;
+                        break;
+                    }
                 }
-            }
+                this.println("unknown register: " + sReg);
-            if (!fValid) {
-                this.println("invalid value: " + sValue);
                 return;
             }
+
             cpu.updateCPU();
             this.println("updated registers:");
         }