ia8251 Innovasic Semiconductor Inc., ia8251 Datasheet - Page 2

• Manufacturer Part Number: ia8251
• Description: Programmable Communication Interface
• Manufacturer: Innovasic Semiconductor Inc.

Programmable Communication Interface
The IA8251 provides an interface between a microprocessor and a serial communications channel.
The IA8251 receives and transmits data in a variety of configurations including 7- or 8-bit data
words, with odd, even , or no parity, and 1 or 2 stop bits. The transmitter and receiver can be
designed for synchronous or asynchronous operation.
A block diagram is shown in Figure 1.
Functional Block Diagram
Figure 1
IA8251
D7:D0
RESET
CLK
CD_n
RD_n
WR_n
CS_n
DSR_n
DTR_n
CTS_n
RTS_n
READ/WRITE
DATA BUS
CONTROL
CONTROL
BUFFER
MODEM
LOGIC
Copyright
INTERNAL DATA
Customer Specific IC Solutions
BUS
1999, InnovASIC Inc.
Advanced Information
UPPER (4)
GROUP A
GROUP A
GROUP B
GROUP B
PORT C
PORT C
LOWER
PORT B
PORT A
(8)
(4)
(8)
TXD
TXRDY
TXEMPTY
TXC_n
RXD
RXRDY
RXC_n
SYNDET_BD
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