diff --git a/readme.md b/readme.md
index c21b086..43e5e42 100644
--- a/readme.md
+++ b/readme.md
@@ -4,4 +4,6 @@
 
 [2. 基站协议](./通讯协议-教育新版-基站部分.md) 
 
-[3. 常用命令](./cmd.txt) 
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+[3. SDK应用部分](./通讯协议-SDK应用部分.md) 
+
+[4. 常用命令](./cmd.txt) 
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