Description
   The low power COMS IMP16C522 is a single device solution for serving two serial input/output ports simultaneously and one fully bi-directional parallel port for the IBM PC ATM PS/2 and compatible systems. The parallel port is full compatible to the Centronics printer port and IBM serial parallel Adapter. Each Universal Asynchronous Receiver and transmitter (UART) is fully programmable.

KEY FEATUREs
● Two fully programmable serial 1/0
   channels (DC TO 512K BAUD )
● Tri-state TTL drive capabilities for
   bi-directional data bus and control bus
   on each channel
● Loopback control for communications
   link fault isolation for each UART
● Line break generation and detection
   for each UART
● Complete status reporting capabilities
● Generation and stripping of serial
   asynchronous data control bits
   (start ,stop parity )
● Programmable baud rate generator
   and modem control signals for each
   channel
● Fully prioritized independent interrupt
   system controls for each channel
● 16byte FIFO buffers on both transmit
   and receive of each channel to reduce
   number of interrupts presented to the
   CPU
● Programmable FIFO threshold loves
   of 1,4,8,or 14,bytes on each channel
● Two modes of DMA signaling
   available for transfer of data
   characters to and from FIFO buffers
● Fully bi-directional centronics
   compatible parallel port direct printer
   interface
● Advanced CMOS low power
   technology with single +5voit supply
● 68-pin PLCC package