SP37E760 Datasheet, PDF (9/78 Pages) SMSC Corporation – 3.3 V I/O CONTROLLER FOR EMBEDDED APPLICATIONS

PIN #
TQFP
QFP
87
89
76
77
79,89
78
79
81,91
81,91
83,93
80,90
82,92
78,88
80,90
83,85
85,87
NAME
SYMBOL
Transmit Data TXD2
2
(Note⁴)
Receive Data RXD1
1
Transmit Data TXD1
1
nRequest to nRTS1
Send
(System
Option)
nRTS2
(SYSOPT)
nData
Terminal
Ready
nDTR1
nDTR2
nClear to
Send
nCTS1
nCTS2
nData Set
Ready
nDSR1
nDSR2
nData Carrier nDCD1
Detect
nDCD2
BUFFER
TYPE
O12PD
DESCRIPTION
Transmit serial data output for port 2.
I
Receiver serial data input for port 1.
O12 Transmit serial data output for port 1.
O6
Active low Request to Send outputs for the Serial
Port. Handshake output signal notifies modem that
the UART is ready to transmit data. This signal can
be programmed by writing to bit 1 of the Modem
Control Register (MCR). The hardware reset will
reset the nRTS signal to inactive mode (high). nRTS
is forced inactive during loop mode operation.
At the trailing edge of hardware reset the nRTS2
inputs is latched to determine the configuration base
address: 0 = INDEX Base I/O Address 3F0 Hex; 1 =
INDEX Base I/O Address 370 Hex.
O6
Active low Data Terminal Ready outputs for the serial
port. Handshake output signal notifies modem that
the UART is ready to establish data communication
link. This signal can be programmed by writing to bit 0
of Modem Control Register (MCR). The hardware
reset will reset the nDTR signal to inactive mode
(high). nDTR is forced inactive during loop mode
operation.
I
Active low Clear to Send inputs for the serial port.
Handshake signal which notifies the UART that the
modem is ready to receive data. The CPU can
monitor the status of nCTS signal by reading bit 4 of
Modem Status Register (MSR). A nCTS signal state
change from low to high after the last MSR read will
set MSR bit 0 to a 1. If bit 3 of the Interrupt Enable
Register is set, the interrupt is generated when nCTS
changes state. The nCTS signal has no effect on the
transmitter. Note: Bit 4 of MSR is the complement of
nCTS.
I
Active low Data Set Ready inputs for the serial port.
Handshake signal which notifies the UART that the
modem is ready to establish the communication link.
The CPU can monitor the status of nDSR signal by
reading bit 5 of Modem Status Register (MSR). A
nDSR signal state change from low to high after the
last MSR read will set MSR bit 1 to a 1. If bit 3 of
Interrupt Enable Register is set, the interrupt is
generated when nDSR changes state. Note: Bit 5 of
MSR is the complement of nDSR.
I
Active low Data Carrier Detect inputs for the serial
port. Handshake signal which notifies the UART that
carrier signal is detected by the modem. The CPU
can monitor the status of nDCD signal by reading bit 7
of Modem Status Register (MSR). A nDCD signal
state change from low to high after the last MSR read
will set MSR bit 3 to a 1. If bit 3 of Interrupt Enable
Register is set, the interrupt is generated when nDCD
changes state. Note: Bit 7 of MSR is the
complement of nDCD.
SMSC DS – SP37E760
Page 9
Rev. 04/13/2001