diff --git a/include/ubixos/bcd.h b/include/ubixos/bcd.h
new file mode 100644
index 0000000..47568a0
--- /dev/null
+++ b/include/ubixos/bcd.h
@@ -0,0 +1,40 @@
+/*-
+ * Copyright (c) 2002-2018 The UbixOS Project.
+ * All rights reserved.
+ *
+ * This was developed by Christopher W. Olsen for the UbixOS Project.
+ *
+ * Redistribution and use in source and binary forms, with or without modification, are permitted
+ * provided that the following conditions are met:
+ *
+ * 1) Redistributions of source code must retain the above copyright notice, this list of
+ *    conditions, the following disclaimer and the list of authors.
+ * 2) Redistributions in binary form must reproduce the above copyright notice, this list of
+ *    conditions, the following disclaimer and the list of authors in the documentation and/or
+ *    other materials provided with the distribution.
+ * 3) Neither the name of the UbixOS Project nor the names of its contributors may be used to
+ *    endorse or promote products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
+ * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef _UBIXOS_BCD_H_
+#define _UBIXOS_BCD_H_
+
+extern const u_char bcd2bin_data[];
+extern const u_char bin2bcd_data[];
+extern const char hex2ascii_data[];
+
+#define bcd2bin(bcd)    (bcd2bin_data[bcd])
+#define bin2bcd(bin)    (bin2bcd_data[bin])
+#define hex2ascii(hex)  (hex2ascii_data[hex])
+
+#endif /* !_UBIXOS_BCD_H_
diff --git a/sys/include/string.h b/sys/include/string.h
index c0df22b..3a285d0 100644
--- a/sys/include/string.h
+++ b/sys/include/string.h
@@ -48,14 +48,6 @@
 char *strtok_r(char *str, const char *sep, char **last);
 char *strstr(const char *s, char *find);
 
-extern const u_char bcd2bin_data[];
-extern const u_char bin2bcd_data[];
-extern const char hex2ascii_data[];
-
-#define bcd2bin(bcd)    (bcd2bin_data[bcd])
-#define bin2bcd(bin)    (bin2bcd_data[bin])
-#define hex2ascii(hex)  (hex2ascii_data[hex])
-
 #define toupper(c) ((c) - 0x20 * (((c) >= 'a') && ((c) <= 'z')))
 #define tolower(c) ((c) + 0x20 * (((c) >= 'A') && ((c) <= 'Z')))
 
diff --git a/sys/lib/kprintf.c b/sys/lib/kprintf.c
index 0a79d24..374cee8 100644
--- a/sys/lib/kprintf.c
+++ b/sys/lib/kprintf.c
@@ -30,6 +30,7 @@
 #include <string.h>
 #include <sys/video.h>
 #include <ubixos/kpanic.h>
+#include <ubixos/bcd.h>
 
 static char *ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper);
 
@@ -66,7 +67,7 @@
    */
   if (vq == 0) {
     /* divide by zero. */
-    static const volatile unsigned int zero = 0;
+        static const volatile unsigned int zero = 0;
 
     tmp.ul[H] = tmp.ul[L] = 1 / zero;
     if (arq)