diff --git a/modules/diskdump/lib/diskdump.js b/modules/diskdump/lib/diskdump.js
index a0903f0ec..650bba1ca 100644
--- a/modules/diskdump/lib/diskdump.js
+++ b/modules/diskdump/lib/diskdump.js
@@ -179,7 +179,7 @@ DiskDump.sNotice = DiskDump.sAPIURL + " " + DiskDump.sCopyright;
 DiskDump.sUsage = "Usage: " + DiskDump.sAPIURL + "?" + DumpAPI.QUERY.PATH + "={url}&" + DumpAPI.QUERY.FORMAT + "=json|data|hex|bytes|img";
 
 /*
- * MY_VOL_LABEL is our default label, used whenever a more suitable label (eg, based on the disk image's folder name)
+ * MY_VOL_LABEL is our default label, used whenever a more suitable label (eg, the disk image's folder name)
  * is not available or not supplied, and MY_OEM_STRING is inserted into any DiskDump-generated diskette images.
  */
 DiskDump.MY_VOL_LABEL = "PCJSDISK";
@@ -192,7 +192,8 @@ DiskDump.MY_OEM_STRING = "PCJS.ORG";
 DiskDump.aDefaultBPBs = [
   [                             // define BPB for 160Kb diskette
     0xEB, 0xFE, 0x90,           // 0x00: JMP instruction, following by 8-byte OEM signature
-    0x49, 0x42, 0x4D, 0x20, 0x20, 0x31, 0x2E, 0x30,     // "IBM  1.0" (this is a fake OEM signature)
+    0x50, 0x43, 0x4A, 0x53, 0x2E, 0x4F, 0x52, 0x47,     // MY_OEM_STRING
+ // 0x49, 0x42, 0x4D, 0x20, 0x20, 0x31, 0x2E, 0x30,     // "IBM  1.0" (this is a fake OEM signature)
     0x00, 0x02,                 // 0x0B: bytes per sector (0x200 or 512)
     0x01,                       // 0x0D: sectors per cluster (1)
     0x01, 0x00,                 // 0x0E: reserved sectors; ie, # sectors preceding the first FAT--usually just the boot sector (1)
@@ -207,7 +208,8 @@ DiskDump.aDefaultBPBs = [
   ],
   [                             // define BPB for 360Kb diskette
     0xEB, 0xFE, 0x90,           // 0x00: JMP instruction, following by 8-byte OEM signature
-    0x49, 0x42, 0x4D, 0x20, 0x20, 0x32, 0x2E, 0x30,     // "IBM  2.0" (this is a real OEM signature)
+    0x50, 0x43, 0x4A, 0x53, 0x2E, 0x4F, 0x52, 0x47,     // MY_OEM_STRING
+ // 0x49, 0x42, 0x4D, 0x20, 0x20, 0x32, 0x2E, 0x30,     // "IBM  2.0" (this is a real OEM signature)
     0x00, 0x02,                 // 0x0B: bytes per sector (0x200 or 512)
     0x02,                       // 0x0D: sectors per cluster (2)
     0x01, 0x00,                 // 0x0E: reserved sectors; ie, # sectors preceding the first FAT--usually just the boot sector (1)
@@ -222,7 +224,8 @@ DiskDump.aDefaultBPBs = [
   ],
   [                             // define BPB for 1.2Mb diskette
     0xEB, 0xFE, 0x90,           // 0x00: JMP instruction, following by 8-byte OEM signature
-    0x49, 0x42, 0x4D, 0x20, 0x31, 0x30, 0x2E, 0x31,     // "IBM 10.0" (which I believe was used on IBM OS/2 1.0 diskettes)
+    0x50, 0x43, 0x4A, 0x53, 0x2E, 0x4F, 0x52, 0x47,     // MY_OEM_STRING
+ // 0x49, 0x42, 0x4D, 0x20, 0x31, 0x30, 0x2E, 0x31,     // "10.0" (which I believe was used on IBM OS/2 1.0 diskettes)
     0x00, 0x02,                 // 0x0B: bytes per sector (0x200 or 512)
     0x01,                       // 0x0D: sectors per cluster (1)
     0x01, 0x00,                 // 0x0E: reserved sectors; ie, # sectors preceding the first FAT--usually just the boot sector (1)
@@ -237,7 +240,8 @@ DiskDump.aDefaultBPBs = [
   ],
   [                             // define BPB for 1.44Mb diskette
     0xEB, 0xFE, 0x90,           // 0x00: JMP instruction, following by 8-byte OEM signature
-    0x4d, 0x53, 0x44, 0x4F, 0x53, 0x35, 0x2E, 0x30,     // "MSDOS5.0" (an actual OEM signature, arbitrarily chosen for use here)
+    0x50, 0x43, 0x4A, 0x53, 0x2E, 0x4F, 0x52, 0x47,     // MY_OEM_STRING
+ // 0x4d, 0x53, 0x44, 0x4F, 0x53, 0x35, 0x2E, 0x30,     // "MSDOS5.0" (an actual OEM signature, arbitrarily chosen for use here)
     0x00, 0x02,                 // 0x0B: bytes per sector (0x200 or 512)
     0x01,                       // 0x0D: sectors per cluster (1)
     0x01, 0x00,                 // 0x0E: reserved sectors; ie, # sectors preceding the first FAT--usually just the boot sector (1)
@@ -252,7 +256,8 @@ DiskDump.aDefaultBPBs = [
   ],
   [                             // define BPB for 10Mb hard disk
     0xEB, 0xFE, 0x90,           // 0x00: JMP instruction, following by 8-byte OEM signature
-    0x49, 0x42, 0x4D, 0x20, 0x20, 0x32, 0x2E, 0x30,     // "IBM  2.0" (this is a real OEM signature)
+    0x50, 0x43, 0x4A, 0x53, 0x2E, 0x4F, 0x52, 0x47,     // MY_OEM_STRING
+ // 0x49, 0x42, 0x4D, 0x20, 0x20, 0x32, 0x2E, 0x30,     // "IBM  2.0" (this is a real OEM signature)
     0x00, 0x02,                 // 0x0B: bytes per sector (0x200 or 512)
     0x08,                       // 0x0D: sectors per cluster (8)
     0x01, 0x00,                 // 0x0E: reserved sectors; ie, # sectors preceding the first FAT--usually just the boot sector (1)
diff --git a/modules/pcjs/lib/x86func.js b/modules/pcjs/lib/x86func.js
index 7431ef82f..72cebce5a 100644
--- a/modules/pcjs/lib/x86func.js
+++ b/modules/pcjs/lib/x86func.js
@@ -206,21 +206,22 @@ X86.fnBOUND = function BOUND(dst, src)
  */
 X86.fnBSF = function BSF(dst, src)
 {
+    var n = 0;
     if (!src) {
         this.setZF();
     } else {
         this.clearZF();
-        var i = 0, bit = 0x1;
+        var bit = 0x1;
         while (bit & this.dataMask) {
             if (src & bit) {
-                dst = i;
+                dst = n;
                 break;
             }
             bit <<= 1;
-            i++;
+            n++;                // TODO: Determine if n should be incremented before the bailout for an accurate cycle count
         }
     }
-    this.nStepCycles -= this.cycleCounts.nOpCyclesBitScan + i * 3;
+    this.nStepCycles -= this.cycleCounts.nOpCyclesBitScan + n * 3;
     return dst;
 };
 
@@ -241,21 +242,23 @@ X86.fnBSF = function BSF(dst, src)
  */
 X86.fnBSR = function BSR(dst, src)
 {
+    var n = 0;
     if (!src) {
         this.setZF();
     } else {
         this.clearZF();
-        var i = (this.dataSize == 2? 15 : 31), j = i, bit = 1 << i;
+        var i = (this.dataSize == 2? 15 : 31), bit = 1 << i;
         while (bit) {
             if (src & bit) {
                 dst = i;
                 break;
             }
             bit >>>= 1;
-            i--;
+            n++; i--;           // TODO: Determine if n should be incremented before the bailout for an accurate cycle count
         }
+
     }
-    this.nStepCycles -= this.cycleCounts.nOpCyclesBitScan + (j - i) * 3;
+    this.nStepCycles -= this.cycleCounts.nOpCyclesBitScan + n * 3;
     return dst;
 };
 
diff --git a/modules/pcjs/lib/x86op0f.js b/modules/pcjs/lib/x86op0f.js
index 4f6fd392c..d5f5b0d99 100644
--- a/modules/pcjs/lib/x86op0f.js
+++ b/modules/pcjs/lib/x86op0f.js
@@ -309,8 +309,6 @@ X86.opMOVcr = function MOVcr()
         this.regCR3 = this.regEBX;
         this.regEBX = temp;
         break;
-    default:
-        break;              // there IS no other case, but JavaScript inspections don't know that
     }
 };
 
diff --git a/modules/pcjs/lib/x86seg.js b/modules/pcjs/lib/x86seg.js
index 7af515a63..131edb16d 100644
--- a/modules/pcjs/lib/x86seg.js
+++ b/modules/pcjs/lib/x86seg.js
@@ -152,6 +152,10 @@ X86Seg.prototype.loadProt = function loadProt(sel, fSuppress)
     var addrDTLimit;
     var cpu = this.cpu;
 
+    /*
+     * Some instructions (eg, CALLF) load a 32-bit value for the selector, while others (eg, LDS) do not;
+     * however, in ALL cases, only the low 16 bits are significant.
+     */
     sel &= 0xffff;
 
     if (!(sel & X86.SEL.LDT)) {