diff --git a/.gitignore b/.gitignore
index bfd3ae4..fb1320b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,12 @@
 # Files generated by build
-/site
\ No newline at end of file
+.vs/
+__vm/
+debug/
+img/
+*.tmp
+*.TMP
+*.sln
+*.vcxproj
+*.vcxproj.filters
+.pioenvs
+.piolibdeps
diff --git a/src/AutoConnectCredentail.cpp b/src/AutoConnectCredentail.cpp
index b5185b2..111e382 100644
--- a/src/AutoConnectCredentail.cpp
+++ b/src/AutoConnectCredentail.cpp
@@ -11,7 +11,7 @@
 #include "AutoConnectCredentail.h"
 
 #define AC_IDENTIFIER "AC_CREDT"
-#define AC_HEADERSIZE ((int)(AC_IDENTIFIER_OFFSET + sizeof(AC_IDENTIFIER) - 1 + sizeof(uint8_t) + sizeof(uint16_t)))
+#define AC_HEADERSIZE ((int)(_offset + sizeof(AC_IDENTIFIER) - 1 + sizeof(uint8_t) + sizeof(uint16_t)))
 
 /**
  *  AutoConnectCredential constructor takes the available count of saved
@@ -33,15 +33,22 @@
  *  Free area are filled with FF, which is reused as an area for insertion.
  */
 AutoConnectCredential::AutoConnectCredential() {
+  AutoConnectCredential(AC_IDENTIFIER_OFFSET);
+}
+
+AutoConnectCredential::AutoConnectCredential(uint16_t offset) {
   char    id_c[sizeof(AC_IDENTIFIER) - 1];
   uint8_t c;
 
+  // Save offset for the credential area.
+  _offset = offset;
+
   EEPROM.begin(AC_HEADERSIZE);
 
   // Validate the save area of the EEPROM.
   // If it is a valid area, retrieve the stored number of entries,
   // if the identifier is not saved, initialize the EEPROM area.
-  for (c = AC_IDENTIFIER_OFFSET; c < AC_IDENTIFIER_OFFSET + sizeof(id_c); c++) {
+  for (c = _offset; c < _offset + sizeof(id_c); c++) {
     id_c[c] = static_cast<char>(EEPROM.read(c));
   }
   if (!strncmp(id_c, AC_IDENTIFIER, sizeof(id_c))) {
diff --git a/src/AutoConnectCredentail.h b/src/AutoConnectCredentail.h
index 7edfa16..b6943b6 100644
--- a/src/AutoConnectCredentail.h
+++ b/src/AutoConnectCredentail.h
@@ -31,6 +31,7 @@ extern "C" {
 class AutoConnectCredential {
  public:
   AutoConnectCredential();
+  AutoConnectCredential(uint16_t offset);
   ~AutoConnectCredential();
   uint8_t   entries() { return _entries; }
   bool      del(const char* ssid);
@@ -44,6 +45,7 @@ class AutoConnectCredential {
   uint16_t  _containSize;   /**< Container size */
   int       _dp;            /**< The current address in EEPROM */
   int       _ep;            /**< The current entry address in EEPROM */
+  uint16_t  _offset;        /**< The offset for the saved area of credentials in EEPROM. */
 };
 
 #endif  // _AUTOCONNECTCREDENTAIL_H_