A modified universal asynchronous receiver transmitter (UART) device is
provided with an auxiliary high speed parallel channel using
supplementary FIFO buffers for the exchange of data. The auxiliary
parallel channel is separate from the normal lower speed serial channel
which is retained in unmodified form. The retained serial channel
provides full compatibility with and support for the National
Semiconductor 16550 standard, while the auxiliary parallel channel allows
for rapid transfer of large data blocks, such as is needed for a PCMCIA
wireless data card for example. The key advantages of this approach lie
both in the data transfer speed and in the reduced amount of development
time needed to implement a UART interface for communicating between a
host computer and a new subsystem. This is because all the UART
functions, except large volume data transfer, can be carried out over the
standard serial channel using standard device drivers.