If your MCU is not already compatible with this librairy you have to create your hown HAL (Hardware Abstraction Layer).
The creation of a new HAL is a big contribution to this project and you will have to pull-request it in the future. To do a good pull request create a new git branch at the poppy_com master level and put all your code inside. When your new HAL is fully operational please pullrequest your branch to contribute to the poppy-project.
Start your new hal by creating a new folder on poppy-com/hal/
You can choose the name of your MCU on your Makefile but you have to give exactly the same name to your new poppy-com/hal/MCU folder.
You can use the HAL template in poppy-com/hal/template/
If you have any question about hal creation please ask!