UARTx_C2 field descriptions (continued)Field Description0 IDLE interrupt requests disabled.1 IDLE interrupt requests enabled.3TETransmitter EnableEnables the UART transmitter. TE can be used to queue an idle preamble by clearing and then setting TE.When C7816[ISO_7816E] is set/enabled and C7816[TTYPE] = 1, this field is automatically cleared afterthe requested block has been transmitted. This condition is detected when TL7816[TLEN] = 0 and fouradditional characters are transmitted.0 Transmitter off.1 Transmitter on.2REReceiver EnableEnables the UART receiver.0 Receiver off.1 Receiver on.1RWUReceiver Wakeup ControlThis field can be set to place the UART receiver in a standby state. RWU automatically clears when anRWU event occurs, that is, an IDLE event when C1[WAKE] is clear or an address match when C1[WAKE]is set. This field must be cleared when C7816[ISO_7816E] is set.NOTE: RWU must be set only with C1[WAKE] = 0 (wakeup on idle) if the channel is currently not idle.This can be determined by S2[RAF]. If the flag is set to wake up an IDLE event and the channelis already idle, it is possible that the UART will discard data. This is because the data must bereceived after an IDLE is detected before IDLE is allowed to reasserted.0 Normal operation.1 RWU enables the wakeup function and inhibits further receiver interrupt requests. Normally, hardwarewakes the receiver by automatically clearing RWU.0SBKSend BreakToggling SBK sends one break character from the following: See Transmitting break characters for thenumber of logic 0s for the different configurations. Toggling implies clearing the SBK field before the breakcharacter has finished transmitting. As long as SBK is set, the transmitter continues to send completebreak characters (10, 11, or 12 bits, or 13 or 14 bits). Ensure that C2[TE] is asserted atleast 1 clock beforeassertion of this bit.• 10, 11, or 12 logic 0s if S2[BRK13] is cleared• 13 or 14 logic 0s if S2[BRK13] is set.This field must be cleared when C7816[ISO_7816E] is set.0 Normal transmitter operation.1 Queue break characters to be sent.Memory map and registersKL27 Sub-Family Reference Manual , Rev. 5, 01/2016686 Freescale Semiconductor, Inc.
