The roboRIO 2.0 has one UART connected to the UART lines on the MXP and one UART connected to the RS-232 port.

The UART lines on the MXP are electrically identical to DIO lines 0 to 13 on the MXP. Like those lines, UART.RX and UART.TX have 40 kΩ pullup resistors to 3.3 V.

The RS-232 lines are compliant with TIA/EIA-232-F voltage levels.