a16450 Universal Asynchronous Receiver/Transmitter Data Sheet
The a16450differs from the National NS16450 device in the following
ways:
Variations &
Clarifications
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The bidirectional bus d[7..0]in the NS16450 is split into an input
bus din[7..0]and an output bus dout[7..0]in the a16450. The
dout[7..0]bus is the direct output of the output data multiplexer,
and is not tri-stated or otherwise affected by the rdor nrdinputs.
In the a16450megafunction, the address registers are implemented
as registers, as opposed to latches in the NS16450 device. These
registers use clkas the clock source and nadsas a clock enable.
The a16450megafunction uses a single clkinput as the primary
clock source. The NS16450 device uses the crystal oscillator interface
(xininput and xoutoutput) as the primary clock source.
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Altera Corporation
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ALTERA [ ALTERA CORPORATION ]
