diff --git a/Makefile b/Makefile
index 19b7646..e0c0246 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,8 @@
 OBJS=abCalc.o abCalcExpr.o abCalcExpReal.o abCalcExprInt.o abCalcStack.o \
     abCalcMode.o abCalcMain.o abCalcOp.o abCalcError.o abCalcOpAdd.o \
     abCalcOpSubtr.o abCalcOpMult.o abCalcOpDiv.o abCalcOpPower.o \
-    abCalcOpAnd.o abCalcOpOr.o abCalcOpXor.o abCalcOpNot.o
+    abCalcOpAnd.o abCalcOpOr.o abCalcOpXor.o abCalcOpNot.o \
+    abCalcOpBin.o abCalcOpOct.o abCalcOpDec.o abCalcOpHex.o
 
 NAME=abCalc
 
@@ -18,16 +19,21 @@ abCalc.o: abCalc.h abCalcExpr.h abCalcMode.h abCalcExpReal.h abCalcExprInt.h \
 abCalcMain.o: abCalc.h abCalcStack.h abCalcExpr.h abCalcOp.h abCalcError.h
 abCalcOp.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpAdd.h \
     abCalcOpSubtr.h abCalcOpMult.h abCalcOpDiv.h abCalcOpPower.h \
-    abCalcOpAnd.h abCalcOpOr.h abCalcOpXor.h abCalcOpNot.h
-abCalcOpAdd.o: abCalcOp.h abCalcError.h abCalcOpAdd.h
-abCalcOpSubtr.o: abCalcOp.h abCalcError.h abCalcOpSubtr.h
-abCalcOpMult.o: abCalcOp.h abCalcError.h abCalcOpMult.h
-abCalcOpDiv.o: abCalcOp.h abCalcError.h abCalcOpDiv.h
-abCalcOpPower.o: abCalcOp.h abCalcError.h abCalcOpPower.h
-abCalcOpAnd.o: abCalcOp.h abCalcError.h abCalcOpAnd.h
-abCalcOpOr.o: abCalcOp.h abCalcError.h abCalcOpOr.h
-abCalcOpXor.o: abCalcOp.h abCalcError.h abCalcOpXor.h
-abCalcOpNot.o: abCalcOp.h abCalcError.h abCalcOpNot.h
+    abCalcOpAnd.h abCalcOpOr.h abCalcOpXor.h abCalcOpNot.h abCalcOpBin.h \
+    abCalcOpOct.h abCalcOpDec.h abCalcOpHex.h
+abCalcOpAdd.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpAdd.h
+abCalcOpSubtr.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpSubtr.h
+abCalcOpMult.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpMult.h
+abCalcOpDiv.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpDiv.h
+abCalcOpPower.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpPower.h
+abCalcOpAnd.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpAnd.h
+abCalcOpOr.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpOr.h
+abCalcOpXor.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpXor.h
+abCalcOpNot.o: abCalcOp.h abCalcError.h abCalcExpr.h abCalcStack.h abCalcOpNot.h
+abCalcOpBin.o: abCalcOp.h abCalcMode.h abCalcOpBin.h
+abCalcOpOct.o: abCalcOp.h abCalcMode.h abCalcOpOct.h
+abCalcOpDec.o: abCalcOp.h abCalcMode.h abCalcOpDec.h
+abCalcOpHex.o: abCalcOp.h abCalcMode.h abCalcOpHex.h
 
 
 $(NAME): $(OBJS)
diff --git a/abCalcExpr.h b/abCalcExpr.h
index 60a20a3..0e1feec 100644
--- a/abCalcExpr.h
+++ b/abCalcExpr.h
@@ -23,7 +23,7 @@ typedef unsigned long abCalcIntType;
 
 #define AB_CALC_EXPR_MAX_INT_WIDTH ((sizeof(abCalcIntType) * 8))
 
-#define AB_CALC_EXPR_STRING_MAX (AB_CALC_EXPR_MAX_INT_WIDTH + 4)
+#define AB_CALC_EXPR_STRING_MAX (AB_CALC_EXPR_MAX_INT_WIDTH + 8)
 
 
 typedef struct abCalcExpr {
diff --git a/abCalcExprInt.c b/abCalcExprInt.c
index f79add9..b9cbd90 100644
--- a/abCalcExprInt.c
+++ b/abCalcExprInt.c
@@ -201,7 +201,7 @@ char *abCalcExprIntFormat(abCalcExpr *expr, char *buffer)
         case abCalcModeBinBase:
 		    gotFirstOne = 0;
             ptr = buffer;
-            *ptr = '*';
+            *ptr = '#';
             ptr++;
 		
 		    for (i = width - 1; i >= 0; i--) {
@@ -220,19 +220,23 @@ char *abCalcExprIntFormat(abCalcExpr *expr, char *buffer)
                 *ptr = '0';
                 ptr++;
             }
+            *ptr = ' ';
+            ptr++;
+            *ptr = 'b';
+            ptr++;
             *ptr = '\0';
             break;
             
         case abCalcModeOctBase:
-            sprintf(buffer, "#%lo", value);
+            sprintf(buffer, "#%lo o", value);
             break;
 
         case abCalcModeDecBase:
-            sprintf(buffer, "#%lu", value);
+            sprintf(buffer, "#%lu d", value);
             break;
 
         case abCalcModeHexBase:
-            sprintf(buffer, "#%lX", value);
+            sprintf(buffer, "#%lX h", value);
             break;
 
         default:
diff --git a/abCalcOp.c b/abCalcOp.c
index a8e4e54..34cbc6f 100644
--- a/abCalcOp.c
+++ b/abCalcOp.c
@@ -17,11 +17,17 @@
 #include "abCalcOpMult.h"
 #include "abCalcOpDiv.h"
 #include "abCalcOpPower.h"
+
 #include "abCalcOpAnd.h"
 #include "abCalcOpOr.h"
 #include "abCalcOpXor.h"
 #include "abCalcOpNot.h"
 
+#include "abCalcOpBin.h"
+#include "abCalcOpOct.h"
+#include "abCalcOpDec.h"
+#include "abCalcOpHex.h"
+
 
 #define AB_CALC_MAX_OPS 128
 
@@ -39,10 +45,16 @@ void abCalcOpInit(void)
     abCalcOpMultInit();
     abCalcOpDivInit();
     abCalcOpPowerInit();
+
     abCalcOpAndInit();
     abCalcOpOrInit();
     abCalcOpXorInit();
     abCalcOpNotInit();
+
+    abCalcOpBinInit();
+    abCalcOpOctInit();
+    abCalcOpDecInit();
+    abCalcOpHexInit();
 }
 
 
diff --git a/abCalcOpBin.c b/abCalcOpBin.c
new file mode 100644
index 0000000..657025a
--- /dev/null
+++ b/abCalcOpBin.c
@@ -0,0 +1,30 @@
+/* 
+    abCalcOpBin.c
+        By: Jeremy Rand
+ */
+
+
+#include <stdio.h>
+
+#include "abCalcOpBin.h"
+
+#include "abCalcOp.h"
+#include "abCalcMode.h"
+
+
+#define OP_NAME "BIN"
+
+
+static void binExecute(void);
+
+
+void abCalcOpBinInit(void)
+{
+    abCalcOpRegister(OP_NAME, binExecute);
+}
+
+
+void binExecute(void)
+{
+    abCalcModeSetBase(abCalcModeBinBase);
+}
diff --git a/abCalcOpBin.h b/abCalcOpBin.h
new file mode 100644
index 0000000..f517b46
--- /dev/null
+++ b/abCalcOpBin.h
@@ -0,0 +1,14 @@
+/* 
+    abCalcOpBin.h
+        By: Jeremy Rand
+ */
+
+
+#ifndef ABCALCOPBIN_H
+#define ABCALCOPBIN_H
+
+
+void abCalcOpBinInit(void);
+
+
+#endif
diff --git a/abCalcOpDec.c b/abCalcOpDec.c
new file mode 100644
index 0000000..5870354
--- /dev/null
+++ b/abCalcOpDec.c
@@ -0,0 +1,30 @@
+/* 
+    abCalcOpDec.c
+        By: Jeremy Rand
+ */
+
+
+#include <stdio.h>
+
+#include "abCalcOpDec.h"
+
+#include "abCalcOp.h"
+#include "abCalcMode.h"
+
+
+#define OP_NAME "DEC"
+
+
+static void decExecute(void);
+
+
+void abCalcOpDecInit(void)
+{
+    abCalcOpRegister(OP_NAME, decExecute);
+}
+
+
+void decExecute(void)
+{
+    abCalcModeSetBase(abCalcModeDecBase);
+}
diff --git a/abCalcOpDec.h b/abCalcOpDec.h
new file mode 100644
index 0000000..4a598a5
--- /dev/null
+++ b/abCalcOpDec.h
@@ -0,0 +1,14 @@
+/* 
+    abCalcOpDec.h
+        By: Jeremy Rand
+ */
+
+
+#ifndef ABCALCOPDEC_H
+#define ABCALCOPDEC_H
+
+
+void abCalcOpDecInit(void);
+
+
+#endif
diff --git a/abCalcOpHex.c b/abCalcOpHex.c
new file mode 100644
index 0000000..4c86a78
--- /dev/null
+++ b/abCalcOpHex.c
@@ -0,0 +1,30 @@
+/* 
+    abCalcOpHex.c
+        By: Jeremy Rand
+ */
+
+
+#include <stdio.h>
+
+#include "abCalcOpHex.h"
+
+#include "abCalcOp.h"
+#include "abCalcMode.h"
+
+
+#define OP_NAME "HEX"
+
+
+static void hexExecute(void);
+
+
+void abCalcOpHexInit(void)
+{
+    abCalcOpRegister(OP_NAME, hexExecute);
+}
+
+
+void hexExecute(void)
+{
+    abCalcModeSetBase(abCalcModeHexBase);
+}
diff --git a/abCalcOpHex.h b/abCalcOpHex.h
new file mode 100644
index 0000000..f5d55c3
--- /dev/null
+++ b/abCalcOpHex.h
@@ -0,0 +1,14 @@
+/* 
+    abCalcOpHex.h
+        By: Jeremy Rand
+ */
+
+
+#ifndef ABCALCOPHEX_H
+#define ABCALCOPHEX_H
+
+
+void abCalcOpHexInit(void);
+
+
+#endif
diff --git a/abCalcOpOct.c b/abCalcOpOct.c
new file mode 100644
index 0000000..c9b3c67
--- /dev/null
+++ b/abCalcOpOct.c
@@ -0,0 +1,30 @@
+/* 
+    abCalcOpOct.c
+        By: Jeremy Rand
+ */
+
+
+#include <stdio.h>
+
+#include "abCalcOpOct.h"
+
+#include "abCalcOp.h"
+#include "abCalcMode.h"
+
+
+#define OP_NAME "OCT"
+
+
+static void octExecute(void);
+
+
+void abCalcOpOctInit(void)
+{
+    abCalcOpRegister(OP_NAME, octExecute);
+}
+
+
+void octExecute(void)
+{
+    abCalcModeSetBase(abCalcModeOctBase);
+}
diff --git a/abCalcOpOct.h b/abCalcOpOct.h
new file mode 100644
index 0000000..b4838c1
--- /dev/null
+++ b/abCalcOpOct.h
@@ -0,0 +1,14 @@
+/* 
+    abCalcOpOct.h
+        By: Jeremy Rand
+ */
+
+
+#ifndef ABCALCOPOCT_H
+#define ABCALCOPOCT_H
+
+
+void abCalcOpOctInit(void);
+
+
+#endif