W83697HF_05 Datasheet, PDF (18/102 Pages) Winbond – LPC I/O

W83697HF
5.4 Serial Port Interface
SYMBOL PIN
I/O
CTSA#
CTSB#
47
55
IN_t
DSRA#
DSRB#
RTSA#
48
56
IN_t
49
O₈
HEFRAS
RTSB#
INcd
57
O₈
DTRA#
PNPCSV#
50
O₈
INcd
58
DTRB#
SINA
51
SINB
59
SOUTA
52
PENROM#
SOUTB
61
PEN48
DCDA#
53
DCDB#
62
RIA#
54
RIB#
63
O₈
IN_t
O₈
INcd
O₈
INcd
IN_t
IN_t
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, and PRT)
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 PENROM#, which provides the power on value for
CR24 bit 1. A 4.7kΩ is recommended if intends to pull up .
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: April 14, 2005
Revision2.0