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MC68341 USER’S MANUAL
MOTOROLA
2.9.3 Receive Data (RxDA, RxDB)
These signals are the receiver serial data input for each channel. Data received on this
signal is sampled on the rising edge of the clock source, with the least significant bit
received first.
2.9.4 Transmit Data (TxDA, TxDB)
These signals are the transmitter serial data output for each channel. The output is held
high ('mark' condition) when the transmitter is disabled, idle, or operating in the local
loopback mode. Data is shifted out on this signal at the falling edge of the clock source,
with the least significant bit transmitted first.
2.9.5 Clear to Send
(CTSA, CTSB)
These active-low signals can be programmed as the clear-to-send inputs for each
channel.
2.9.6 Request to Send
(RTSA/OP0, RTSB / OP1)
These active-low signals can be programmed as request-to-send outputs or used as
discrete outputs.
RTSB, RTSA
When used for this function, these signals function as the request-to-send outputs.
OP1, OP0
When used for this function, these outputs are controlled by the value of bit 1 and bit 0,
respectively, in the output port data registers.
2.9.7 Transmitter Ready
(TRDYA / OP6)
This active-low output can be programmed as the channel A transmitter ready status
indicator or used as a discrete output.
TRDYA
When used for this function, this signal reflects the complement of the status of bit 2 of
the channel A status register. This signal can be used to control parallel data flow by
acting as an interrupt to indicate when the transmitter contains a character.
OP6
When used for this function, this output is controlled by bit 6 in the output port data
registers.
2.9.8 Receiver Ready
(RRDYA / FFULLA/ OP4)
This active-low output signal can be programmed as the channel A receiver ready,
channel A FIFO full indicator, or a dedicated parallel output.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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