diff --git a/libsrc/cbm/Makefile b/libsrc/cbm/Makefile
index 4fd88a2a9..3daa254af 100644
--- a/libsrc/cbm/Makefile
+++ b/libsrc/cbm/Makefile
@@ -79,6 +79,7 @@ S_OBJS =	c_acptr.o	\
                 scratch.o       \
                 sysremove.o     \
                 sysrename.o     \
+                toascii.o       \
 		wherex.o        \
                 wherey.o        \
                 write.o
diff --git a/libsrc/cbm/toascii.s b/libsrc/cbm/toascii.s
new file mode 100644
index 000000000..bea7ca880
--- /dev/null
+++ b/libsrc/cbm/toascii.s
@@ -0,0 +1,38 @@
+;
+; Ullrich von Bassewitz, 2009-11-02
+;
+; unsigned char __fastcall__ toascii (unsigned char c);
+; /* Convert a target specific character to ascii */
+;
+
+       	.export	       	_toascii
+
+        .macpack        generic
+
+.proc   _toascii
+
+; Check for code between 65 and 90
+
+        cmp     #$41
+        blt     @L1
+        cmp     #$5B
+        bge     @L1
+
+; Code between 65 and 90
+
+        ora     #$20
+        rts
+
+; Check for code between 193 and 219
+
+@L1:    cmp     #$C1
+        blt     @L9
+        cmp     #$DC
+        bge     @L9
+
+; Code between 193 and 219
+
+        and     #$7F
+@L9:    rts
+
+.endproc