Hello, my name is Ilya.
I have experience with Atmel controllers. Completed projects display 16x2 with interface RS-485, lock with RFID card reader and RS-485 Interface. At my current job.
I have a ready-made module to ensure efficient operation of RS-485 interface and WINSTAR Display 16x2.
Since these projects require debugging, I can do it on my existing microcontroller, and then transfer the code on your system. Or send the code in parts so that you could see it working. I can also write a small application to Linux OS for testing (for an extra charge). I also have expiriens to work with converter USB-RS485 on FT2232.
Best regards, Ilya.