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Serial Controller Module
D23 R/W CTSTX 0 Enable the transmitter with active CTS
Supports hardware handshaking. When
CTSTX is set, the transmitter operates only
when the external CTS signal is in the active
state. An external device can use CTS to
temporarily stall data transmission.
D22 R/W RTSRX 0 Enable active RTS (only when RX FIFO has
space)
Supports hardware handshaking. When
RTSRX is set, the RTS output provides the
receiver FIFO almost-full condition. When the
receiver FIFO backs up, the RTS signal is
dropped. The RTS output stalls an external
transmitter from delivering data.
D21 R/W RL 0 Remote loopback
Provides a remote loopback feature. When set
to 1, the TXD transmit output is connected to
the RXD receive input. The RL field
immediately echoes receive data back as
transmit data.
Primarily used as test vehicle for external data
equipment.
D20 R/W LL 0 Local loopback
Provides an internal local loopback feature.
When set to 1, the internal receive data stream
is connected to the TXD output signal. This
field connects the serial channel receiver
directly to the serial channel transmitter.
Primarily used as a test vehicle for the serial
channel driver firmware.
D19:18 R/W OUT1/OUT2 0 General-purpose output 1/General-purpose
output 2
The OUT1 and OUT2 fields provide extra,
miscellaneous serial channel control signal
outputs. The OUT1 and OUT2 signals can be
routed through PORTA and PORTC pins using
PORTA and PORTC special function modes.
Bits Access Mnemonic Reset Description
Table 85: Serial Channel Control Register A