diff --git a/documents/readme.txt b/documents/readme.txt
index 137c95b8..caeaadf3 100644
--- a/documents/readme.txt
+++ b/documents/readme.txt
@@ -1,2 +1,2 @@
-SDK Development Guide @ http://bbs.espressif.com/viewtopic.php?f=51&t=1023
-All documentations @ http://bbs.espressif.com/viewforum.php?f=51
+SDK Development Guide @ https://espressif.com/sites/default/files/documentation/2a-esp8266-sdk_getting_started_guide_en.pdf
+All documentations @ https://espressif.com/en/support/download/documents?keys=&field_type_tid%5B%5D=14