dmam=mode_0, rt=one_character, tft=empty
UART FIFO Control Register
| fifoe | |
| rfifor | |
| xfifor | |
| dmam | 0 (mode_0): undefined 1 (mode_1): undefined |
| tft | 0 (empty): undefined 1 (two_characters): undefined 2 (quarter_full): undefined 3 (half_full): undefined |
| rt | 0 (one_character): undefined 1 (quarter_full): undefined 2 (half_full): undefined 3 (two_less_than_full): undefined |