diff --git a/src/dev/txt_f256.c b/src/dev/txt_f256.c
index 4b47a50..40f8471 100644
--- a/src/dev/txt_f256.c
+++ b/src/dev/txt_f256.c
@@ -409,6 +409,22 @@ static short txt_f256_set_color(unsigned char foreground, unsigned char backgrou
 extern void io_copy_down(uint16_t count, uint16_t dest, uint16_t src);
 extern void io_copy_up(uint16_t count, uint16_t dest, uint16_t src);
 
+/**
+ * Copy data in the I/O space using the MVN/MVP instructions
+ * 
+ * @param count the number of bytes to copy
+ * @param dest the address within the I/O bank to copy to
+ * @param src the address within the I/O bank to copy from
+ */
+static void io_copy(uint16_t count, uint16_t dest, uint16_t src) {
+	if (dest < src) {
+		io_copy_down(count, dest, src);
+	} else {
+		io_copy_up(count, dest, src);
+	}
+}
+
+
 /**
  * Scroll the screen for the most common case: full screen scrolls up by one full row.
  */
@@ -501,20 +517,20 @@ static void txt_f256_scroll_complex(short horizontal, short vertical) {
 		// Move the rows up
 		uint16_t count = x2 - x0;
 
-		// uint16_t text_dest = (uint16_t)((uint32_t)tvky_text_matrix & 0xffff) + offset_dst;
-		// uint16_t text_src =  (uint16_t)((uint32_t)tvky_text_matrix & 0xffff) + offset_src;
-		// txt_f256_copy(text_dest, text_src, count); 
+		uint16_t text_dest = (uint16_t)((uint32_t)tvky_text_matrix & 0xffff) + offset_dst;
+		uint16_t text_src =  (uint16_t)((uint32_t)tvky_text_matrix & 0xffff) + offset_src;
+		io_copy(count, text_dest, text_src); 
 
-		// uint16_t color_dest = (uint16_t)((uint32_t)tvky_color_matrix & 0xffff) + offset_dst;
-		// uint16_t color_src = (uint16_t)((uint32_t)tvky_color_matrix & 0xffff) + offset_src;
-		// txt_f256_copy(color_dest, color_src, count); 
+		uint16_t color_dest = (uint16_t)((uint32_t)tvky_color_matrix & 0xffff) + offset_dst;
+		uint16_t color_src = (uint16_t)((uint32_t)tvky_color_matrix & 0xffff) + offset_src;
+		io_copy(count, color_dest, color_src);
 
-        for (x = x0; x != x2; x += dx) {
-            offset_dst += dx;
-            offset_src += dx;
-            tvky_text_matrix[offset_dst] = tvky_text_matrix[offset_src];
-            tvky_color_matrix[offset_dst] = tvky_color_matrix[offset_src];
-        }
+        // for (x = x0; x != x2; x += dx) {
+        //     offset_dst += dx;
+        //     offset_src += dx;
+        //     tvky_text_matrix[offset_dst] = tvky_text_matrix[offset_src];
+        //     tvky_color_matrix[offset_dst] = tvky_color_matrix[offset_src];
+        // }
     }
 
     /* Clear the rectangles */
diff --git a/src/version.h b/src/version.h
index c182d22..d722354 100644
--- a/src/version.h
+++ b/src/version.h
@@ -7,6 +7,6 @@
 
 #define VER_MAJOR 1
 #define VER_MINOR 1
-#define VER_BUILD 11
+#define VER_BUILD 12
 
 #endif