diff --git a/include/tgi.h b/include/tgi.h
index f458180c5..15a6437cc 100644
--- a/include/tgi.h
+++ b/include/tgi.h
@@ -134,7 +134,7 @@ void __fastcall__ tgi_setdrawpage (unsigned char page);
 /* Set the drawable page. Will set an error if the page is not available. */
 
 unsigned char tgi_getcolorcount (void);
-/* Get the number of available colors. */
+/* Get the number of available colors. Zero means 256 colors. */
 
 unsigned char tgi_getmaxcolor (void);
 /* Return the maximum supported color number (the number of colors would
diff --git a/libsrc/tgi/tgi_setcolor.s b/libsrc/tgi/tgi_setcolor.s
index 8e6fdc555..16f075767 100644
--- a/libsrc/tgi/tgi_setcolor.s
+++ b/libsrc/tgi/tgi_setcolor.s
@@ -1,5 +1,6 @@
 ;
-; Ullrich von Bassewitz, 21.06.2002
+; 2002-06-21, Ullrich von Bassewitz
+; 2020-06-04, Greg King
 ;
 ; void __fastcall__ tgi_setcolor (unsigned char color);
 ; /* Set the current drawing color */
@@ -11,9 +12,11 @@
 
         cmp     _tgi_colorcount ; Compare to available colors
         bcs     @L1
-        sta     _tgi_color      ; Remember the drawing color
+@L0:    sta     _tgi_color      ; Remember the drawing color
         jmp     tgi_setcolor    ; Call the driver
-@L1:    jmp     tgi_inv_arg     ; Invalid argument
+
+@L1:    ldx     _tgi_colorcount
+        beq     @L0             ; Zero means 256 colors
+        jmp     tgi_inv_arg     ; Invalid argument
 
 .endproc
-