I made this suit follow your instructions, but the FPS is only 6-7fps

[jxx315]

I made this suit follow your instructions, but the FPS is only 6-7fps.
I made the test about running time of arduino loop(from get 'a' to send data to host)：the result is 27ms . but when run the the game engine ,the FPS is only 6-7fps .
My host computer:
OS ：win7
CPU： i5-4590
RAM: 8GB
Graphics card：AMD Radeon R9 200 Series (2048MB)
I do not know the reason. Can you help me？ thank u