GENERAL DESCRIPTION
The ST16C550 (550) is a universal asynchronous receiver
and transmitter with 16 byte transmit and receive
FIFO. It operates at 2.97 to 5.5 volts. A programmable
baud rate generator can select transmit and receive
clock rates from 50 bps to 1.5 Mbps.
The ST16C550 is an improved version of the NS16C550
UART with higher operating speed and lower access
time. The ST16C550 on board status registers provides
the error conditions, type and status of the transfer
operation being performed. Included is complete MODEM
control capability, and a processor interrupt
system that may be software tailored to the user’s
requirements. The ST16C550 provides internal loopback
capability for on board diagnostic testing.
The ST16C550 is available in 40 pin PDIP, 44 pin PLCC,
and 48 pin TQFP packages. It is fabricated in an
advanced CMOS process to achieve low drain power
and high speed requirements.

FEATURES
· Pin to pin and functionally compatible to the Industry
Standard 16C550
· 2.97 to 5.5 volt operation
· 24MHz clock operation at 5V
· 16MHz clock operation at 3.3V
· 16 byte transmit FIFO
· 16 byte receive FIFO with error flags
· Full duplex operation
· Transmit and receive control
· Four selectable receive FIFO interrupt trigger levels
· Standard modem interface
· Compatible with ST16C450
· Low operating current ( 1.2mA typ.)