MC68306FC16 Datasheet, PDF (31/191 Pages) Motorola, Inc – Integrated EC000 Processor

2.6.1 Channel A Receiver Serial-Data Input (RxDA)
This signal is the receiver serial-data input for channel A. The least-significant bit is
received first. Data on this pin is sampled on the rising edge of the programmed clock
source.
2.6.2 Channel A Transmitter Serial-Data Output (TxDA)
This signal is the transmitter serial-data output for channel A. The least-significant bit is
transmitted first. This output is held high (mark condition) when the transmitter is disabled,
idle, or operating in the local loopback mode. (Mark is high and space is low). Data is
shifted out this pin on the falling edge of the programmed clock source.
2.6.3 Channel B Receiver Serial-Data Input (RxDB)
This signal is the receiver serial-data input for channel B. The least-significant bit is
received first. Data on this pin is sampled on the rising edge of the programmed clock
source.
2.6.4 Channel B Transmitter Serial-Data Output (TxDB)
This signal is the transmitter serial-data output for channel B. The least-significant bit is
transmitted first. This output is held high (mark condition) when the transmitter is disabled,
idle, or operating in the local loopback mode. Data is shifted out of this pin on the falling
edge of the programmed clock source.
2.6.5 CTSA
This input can be used as the channel A clear-to-send active low input (CTSA) or general -
purpose input (IP0). A change-of-state detector is also associated with this input.
2.6.6 RTSA
This output can be used as the channel A active low request-to-send (RTSA) output, or a
general-purpose output (OP0). When used as RTSA, it is automatically negated and
reasserted by either the receiver or transmitter.
2.6.7 CTSB
This input can be used as the channel B clear-to-send active low input (CTSB) or general -
purpose input. A change-of-state detector is also associated with this input.
2.6.8 RTSB
This output can be used as a general-purpose output or the channel B active low request-
to-send (RTSB) output. When used for this function, it is automatically negated and
reasserted by either the receiver or transmitter.
MOTOROLA
MC68306 USER'S MANUAL
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