W83627HF Datasheet, PDF (24/185 Pages) Winbond – WINBOND I/O

W83627HF/F
PRELIMINARY
1.4 Serial Port Interface
SYMBOL PIN
I/O
CTSA#
CTSB#
49
IN_t
78
DSRA#
DSRB#
RTSA#
50
IN_t
79
51
I/O_8t
HEFRAS
RTSB#
DTRA#
80
I/O_8t
52
I/O_8t
PNPCSV#
DTRB#
SINA
SINB
SOUTA
PENKBC
81
I/O_8t
53
IN_t
82
54
I/O_8t
SOUTB
PEN48
DCDA#
DCDB#
RIA#
RIB#
83
I/O_8t
56
IN_t
84
57
IN_t
85
FUNCTION
Clear To Send. It is the modem control input.
The function of these pins can be tested by reading bit 4 of the
handshake status register.
Data Set Ready. An active low signal indicates the modem or data
set is ready to establish a communication link and transfer data to
the UART.
UART A Request To Send. An active low signal informs the
modem or data set that the controller is ready to send data.
During power-on reset, this pin is pulled down internally and is
defined as HEFRAS, which provides the power-on value for CR26
bit 6 (HEFRAS). A 4.7 kΩ is recommended if intends to pull up.
(select 4EH as configuration I/O port′s address)
UART B Request To Send. An active low signal informs the
modem or data set that the controller is ready to send data.
UART A Data Terminal Ready. An active low signal informs the
modem or data set that the controller is ready to communicate.
During power-on reset, this pin is pulled down internally and is
defined as _PNPCSV#, which provides the power-on value for CR24
bit 0 (PNPCSV#). A 4.7 kΩ is recommended if intends to pull up.
(clear the default value of FDC, UARTs, PRT, Game port and MIDI
port)
UART B Data Terminal Ready. An active low signal informs the
modem or data set that controller is ready to communicate.
Serial Input. It is used to receive serial data through the
communication link.
UART A Serial Output. It is used to transmit serial data out to the
communication link.
During power-on reset, this pin is pulled down internally and is
defined as PENKBC, which provides the power-on value for CR24
bit 2 (ENKBC). A 4.7 kΩ resistor is recommended if intends to pull
up. (enable KBC)
UART B Serial Output. During power-on reset, this pin is pulled
down internally and is defined as PEN48, which provides the
power-on value for CR24 bit 6 (EN48). A 4.7 kΩ resistor is
recommended if intends to pull up.
Data Carrier Detect. An active low signal indicates the modem or
data set has detected a data carrier.
Ring Indicator. An active low signal indicates that a ring signal is
being received from the modem or data set.
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Publication Release Date: Jul 1999
Revision 0.53