diff --git a/include/tgi.h b/include/tgi.h
index adda65658..d43ebeecb 100644
--- a/include/tgi.h
+++ b/include/tgi.h
@@ -6,7 +6,7 @@
 /*                                                                           */
 /*                                                                           */
 /*                                                                           */
-/* (C) 2002-2003 Ullrich von Bassewitz                                       */
+/* (C) 2002-2004 Ullrich von Bassewitz                                       */
 /*               Römerstrasse 52                                             */
 /*               D-70794 Filderstadt                                         */
 /* EMail:        uz@cc65.org                                                 */
@@ -209,6 +209,12 @@ void __fastcall__ tgi_outtextxy (int x, int y, const char* s);
  * the end of the text.
  */
 
+unsigned __fastcall__ tgi_ioctl (unsigned char code, unsigned val);
+/* Call the driver specific control function. What this function does for
+ * a specific code depends on the driver. The driver will set an error
+ * for unknown codes or values.
+ */
+
 
 
 /* End of tgi.h */
diff --git a/libsrc/tgi/Makefile b/libsrc/tgi/Makefile
index 4ffea9d01..3f13d37ae 100644
--- a/libsrc/tgi/Makefile
+++ b/libsrc/tgi/Makefile
@@ -41,6 +41,7 @@ S_OBJS =       	tgi-kernel.o   	        \
                 tgi_getyres.o           \
                 tgi_gotoxy.o            \
                 tgi_init.o              \
+                tgi_ioctl.o             \
                 tgi_line.o              \
                 tgi_linepop.o           \
                 tgi_lineto.o            \
diff --git a/libsrc/tgi/tgi_ioctl.s b/libsrc/tgi/tgi_ioctl.s
new file mode 100644
index 000000000..35542f3ce
--- /dev/null
+++ b/libsrc/tgi/tgi_ioctl.s
@@ -0,0 +1,26 @@
+;
+; Ullrich von Bassewitz, 2004-10-14
+;
+; unsigned __fastcall__ tgi_ioctl (unsigned char code, unsigned val);
+; /* Call the driver specific control function. What this function does for
+;  * a specific code depends on the driver. The driver will set an error
+;  * for unknown codes or values.
+;  */
+;
+
+        .include        "tgi-kernel.inc"
+
+        .import         popa
+        .importzp       ptr1
+
+
+.proc   _tgi_ioctl
+
+        sta     ptr1
+        stx     ptr1+1          ; Save val
+        jsr     popa            ; Retrieve code
+        jmp     tgi_control     ; Call the driver
+
+.endproc
+
+