Serial Communications Interface Module (SCI)
13.6 I/O Signals
Port F shares two of its pins with the SCI module. The two SCI input/output (I/O)
pins are:
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PTF5/TxD — Transmit data
PTF4/RxD — Receive data
13.6.1 PTF5/TxD (Transmit Data)
The PTF5/TxD pin is the serial data output from the SCI transmitter. The SCI
shares the PTF5/TxD pin with port F. When the SCI is enabled, the PTF5/TxD pin
is an output regardless of the state of the DDRF5 bit in data direction register F
(DDRF).
13.6.2 PTF4/RxD (Receive Data)
The PTF4/RxD pin is the serial data input to the SCI receiver. The SCI shares the
PTF4/RxD pin with port F. When the SCI is enabled, the PTF4/RxD pin is an input
regardless of the state of the DDRF4 bit in data direction register F (DDRF).
13.7 I/O Registers
These I/O registers control and monitor SCI operation:
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SCI control register 1 (SCC1)
SCI control register 2 (SCC2)
SCI control register 3 (SCC3)
SCI status register 1 (SCS1)
SCI status register 2 (SCS2)
SCI data register (SCDR)
SCI baud rate register (SCBR)
13.7.1 SCI Control Register 1
SCI control register 1 (SCC1):
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Enables loop-mode operation
Enables the SCI
Controls output polarity
Controls character length
Controls SCI wakeup method
Controls idle character detection
Enables parity function
Controls parity type
Data Sheet
182
MC68HC908MR32 • MC68HC908MR16 — Rev. 6.0
Serial Communications Interface Module (SCI) MOTOROLA
FREESCALE [ Freescale ]
