1 files changed, 19 insertions, 3 deletions
diff --git a/os/hal/dox/serial_usb.dox b/os/hal/dox/serial_usb.dox
index 0f857052b..4384a59f8 100644
--- a/os/hal/dox/serial_usb.dox
+++ b/os/hal/dox/serial_usb.dox
@@ -31,9 +31,25 @@
  * functionalities can be used in any moment, any transition not explicitly
  * shown in the following diagram has to be considered an error and shall
  * be captured by an assertion (if enabled).
- * @if LATEX_PDF
- * @else
- * @endif
+ * @dot
+  digraph example {
+    rankdir="LR";
+    node [shape=circle, fontname=Helvetica, fontsize=8, fixedsize="true",
+          width="0.9", height="0.9"];
+    edge [fontname=Helvetica, fontsize=8];
+
+    uninit [label="SDU_UNINIT", style="bold"];
+    stop [label="SDU_STOP\nLow Power"];
+    ready [label="SDU_READY\nClock Enabled"];
+
+    uninit -> stop [label=" sduInit()"];
+    stop -> stop [label="\nsduStop()"];
+    stop -> ready [label="\nsduStart()"];
+    ready -> stop [label="\nsduStop()"];
+    ready -> ready [label="\nsduStart()"];
+    ready -> ready [label="\nAny I/O operation"];
+  }
+ * @enddot
  *
  * @ingroup IO
  */