COM81C17
Twent y Pin UART (TPUART)
FEATURES
! Single Chip UART With Baud Rate
Generator
! Asynchronous Operation
- 16 Selectable Baud Rate Clock
Frequencies (Internal)
- External 16x Clock (100 KBaud)
- Character Length: 7 or 8 Bits
- 1 or 2 Stop Bit Selection
! Small 20 Pin DIP (300 mil) or PLCC
! Full or Half Duplex Operation
! Double Buffering of Data
! Programmable Interrupt Generation
! Programmable Modem/Terminal Signals
! Odd or Even Parity Generate and Detect
! Parity, Overrun and Framing Error Detection
! TTL Compatible Inputs and Outputs
! High Speed Host Bus Operation (with no
wait state)
! Low Power CMOS
! Single +5V Power Supply
GENERAL DESCRIPTION
The COM81C17 TPUART is an asynchronous
only receiver/transmitter with a built in
programmable baud rate generator housed in a
twenty pin package. The TPUART receives
serial data streams and converts them into
parallel data characters for the processor. While
receiving serial data, the TPUART will also
accept data characters from the processor in
parallel format and convert them into serial
format along with start, stop and optional parity
bus. The TPUART will signal the processor via
interrupt when it has completely transmitted or
received a character and requires service.
Complete status information is available to the
processor through the status register. The
TPUART features two general purpose control
pins that can be individually programmed to
perform as terminal or modem control
handshake signals.