M68HC11K_13 Datasheet, PDF (163/290 Pages) Freescale Semiconductor, Inc – M68HC11K Family Technical Data

Freescale Semiconductor, Inc.
Serial Communications Interface (SCI)
SCI Registers
TDRE — Transmit Data Register Empty Flag
TDRE is set when the SCDR transfers its contents to the transmission
shift register.
0 = SCDR is full.
1 = SCDR is empty.
TC — Transmit Complete Flag
TC is set when the final character in a message has been sent (no
data, preamble, or break transmissions pending).
0 = Transmitter busy
1 = Transmitter idle
RDRF — Receive Data Register Full Flag
RDRF is set when the shift register has received a complete character
and transferred it to the receive data register.
0 = RDR not full
1 = RDR full
IDLE — Idle Line Detected Flag
IDLE is set when a frame of all 1s is received after a message.
0 = RxD line is active.
1 = RxD line is idle.
OR — Overrun Error Flag
OR is set if a new character is received before a previously received
character is read from SCDR.
0 = No overrun
1 = Overrun detected
NF — Noise Error Flag
NF is set after the last bit in a frame is received if the samples in the
receiver’s data recovery circuit are not unanimous for any of the bits,
including start and stop bits.
0 = No noise detected
1 = Noise detected
M68HC11K Family
MOTOROLA
Serial Communications Interface (SCI)
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Technical Data
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