WampServer

I can't connect to oracle using wampserver php if php.ini include extension=php_oci8_12c.dll instead of extension=php_oci8_11g.dll.
When I run a PHP scripts I get This connection error:

"Fatal error: Call to undefined function oci_pconnect() in c:\wamp\www\PHPScript1.php"
Since the installation did not include php_oci8_12c.dll file I tried several files I found, versions 5.5.4.0 , 5.6.2, 5.6.11, 5.6.14. None worked. The file that worked was php_oci8_11g.dll version 5.5.12.
Oracle Server, Client, Apache and PHP are on the same windoes server.
Installation file: wampserver2.5-Apache-2.4.9-Mysql-5.6.17-php5.5.12-64b.exe.

Software and hardware details:

Wampserver (64 bits & PHP 5.5) 2.5
Apache : 2.4.9 MySQL : 5.6.17 PHP : 5.5.12 PHPMyAdmin : 4.1.14 SqlBuddy : 1.3.3 XDebug : 2.2.5

Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
Full oracle client Version 12.1.0.2.0

OS Name Microsoft Windows Server 2012 R2 DataCenter
Version 6.3.9600 Built 9600
System Manufacturer VMware Inc.
System Type x64-based PC