diff --git a/docs/en/unit/cardkb.md b/docs/en/unit/cardkb.md
index 00fdb328..6a27de23 100644
--- a/docs/en/unit/cardkb.md
+++ b/docs/en/unit/cardkb.md
@@ -36,7 +36,7 @@
 
 - **[Forum](http://forum.m5stack.com/)**
 
-- **[The Firmware of inside MEGA328](https://github.com/m5stack/M5-ProductExampleCodes/tree/master/Unit/CARDKB/firmware_328p)**
+- **[The Firmware of inside MEGA328](https://github.com/m5stack/M5-ProductExampleCodes/tree/master/Unit/CARDKB/firmware_328p/CardKeyBoard)**
 
 ## Example
 
diff --git a/docs/ja/unit/cardkb.md b/docs/ja/unit/cardkb.md
index 2e131670..81272720 100644
--- a/docs/ja/unit/cardkb.md
+++ b/docs/ja/unit/cardkb.md
@@ -36,7 +36,7 @@
 
 - **[フォーラム](http://forum.m5stack.com/)**
 
-- **[ATmega328pのファームウェア](https://github.com/m5stack/M5-ProductExampleCodes/tree/master/Unit/CARDKB/firmware_328p)**
+- **[ATmega328pのファームウェア](https://github.com/m5stack/M5-ProductExampleCodes/tree/master/Unit/CARDKB/firmware_328p/CardKeyBoard)**
 
 ## サンプルコード
 
diff --git a/docs/zh_CN/unit/cardkb.md b/docs/zh_CN/unit/cardkb.md
index cca08ac2..d41a5a30 100644
--- a/docs/zh_CN/unit/cardkb.md
+++ b/docs/zh_CN/unit/cardkb.md
@@ -39,7 +39,7 @@
 
 - **[官方论坛](http://forum.m5stack.com/)**
 
-- **[模块内MEGA328固件](https://github.com/m5stack/M5-ProductExampleCodes/tree/master/Unit/CARDKB/firmware_328p)**
+- **[模块内MEGA328固件](https://github.com/m5stack/M5-ProductExampleCodes/tree/master/Unit/CARDKB/firmware_328p/CardKeyBoard)**
 
 ## 例程