How to add realtek ameba core files:

You can reference below link to get start: http://www.amebaiot.com/ameba-arduino-getting-started/

Or you can follow steps to setup.

1. Arduino IDE 1.6.5 support third party hardware by providing hardware configuration.
You need add Ameba's configuration in "File" -> "Preferences".
And fill below URL in "Additional Boards Manager URLs:
  https://github.com/ambiot/amb1_arduino/raw/master/Arduino_package/package_realtek_ameba1_index.json 
  or https://github.com/ambiot/amb1_arduino/raw/master/Arduino_package/package_realtek.com_ameba1_index.json

We also suggest to enable "Show verbose output" options on "compilation" and "upload" in Preference.

2. Open "Device Manager" in "Tolls" -> "Board" -> "Board Manager".
Wait for IDE update core configuration. Scroll down the menu, you will see Realtek Ameba in the list.
Press "Install" at the right side.

3. Select Ameba in "Tools" -> "Board" -> "Ameba Arduino".
Now you are able to develop Arduino code and upload image onto Ameba.