Arduino IDE not showing Anet board

[txdisco1]

So I just got a anet a6 to play around with and I want to put marlin on it. I using the arduino IDE to talk to the board. I have the marlin config files in there and the anet board details in there but arduino doesn't show an option for the anet board. I working off a mac and have the driver downloaded and arduino recognized the comm port but doesnt show the proper anet board. what should I do?

[txdisco1]

the error i get when compiling is #error "No FastIO definition for the selected AVR Board."

[benebrady]

Go to the board manager and install the Sanguino board library

[txdisco1]

Theres no option for that

[txdisco1]

Ive tried to do this on Mac and pc and I dont see the board in the drop down. Its like the hardware files arent telling arduino what board is supposed to be loaded. When I try to get board info it just says "unknown board"