diff --git a/Documentation/NuttxPortingGuide.html b/Documentation/NuttxPortingGuide.html
index b1cf8b5918b..d2e440e5b5a 100644
--- a/Documentation/NuttxPortingGuide.html
+++ b/Documentation/NuttxPortingGuide.html
@@ -2363,7 +2363,7 @@ else
   which requires the following base functions to read and set time:
 </p>
 <ul>
-  <li><code>up_rtcinitialize()</code>.
+  <li><code>up_rtc_initialize()</code>.
      Initialize the hardware RTC per the selected configuration.
      This function is called once during the OS initialization sequence
   </li>