I have your controller LPC5512JBD100E. what environment do I have to install for it ? I need each thing (IDE, SDK,...) ? Could you send me links for that and explain how to do it ?
I highly recommend you to use MCUXpresso IDE to develop and debug your projects. You can download it in here.
Also, the SDK library will help you develop your applications providing drivers, middleware and example applications. Please click here to download the SDK.