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Signal Definitions
(Continued)
2.4.11 Serial Ports (UARTs) Interface Signals
Signal Name
Ball No.
Type
Description
Mux
EBGA
TEPBGA
SIN1
D26
AG2
I
Serial Inputs.
Receive composite serial data
from the communications link (peripheral
device, modem or other data transfer device).
Note:
If selected as SIN2 or SIN3 func-
tion(s) but not used, then signal(s)
should be tied high.
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SIN2
AJ4
E28
SDTEST3
SIN3
J28
AK8
IRRX1
SOUT1
B27
AF3
O
Serial Outputs.
Send composite serial data
to the communications link (peripheral
device, modem or other data transfer device).
These signals are set active high after a sys-
tem reset.
CLKSEL1 (Strap)
SOUT2
AK3
D29
CLKSEL2 (Strap)
SOUT3
J3
C11
IRTX
RTS2#
AH4
C30
O
Request to Send.
When low, indicates to the
modem or other data transfer device that the
corresponding UART is ready to exchange
data. A system reset sets these signals to
inactive high, and loopback operation holds
them inactive.
GPIO7+
IDE_DACK1#
CTS2#
AJ2
C31
I
Clear to Send.
When low, indicates that the
modem or other data transfer device is ready
to exchange data.
Note:
If selected as CTS2# function but not
used, tie CTS2# low.
GPIO8+
IDE_DREQ1
DTR1#/BOUT1
A28
AG1
O
Data Terminal Ready Outputs.
When low,
indicate to the modem or other data transfer
device that the UART is ready to establish a
communications link. After a system reset,
these balls provide the DTR# function and
set these signals to inactive high. Loopback
operation drive them inactive.
Baud Outputs.
Provide the associated serial
channel baud rate generator output signal if
test mode is selected (i.e., bit 7 of the EXCR1
Register is set).
GPIO18
DTR2#/BOUT2
AH3
D28
GPIO6+IDE_IOR1#
RI2#
H30
AJ8
I
Ring Indicator.
When low, indicates to the
modem that a telephone ring signal has been
received by the modem. They are monitored
during power-off for wakeup event detection.
Note:
If selected as RI2# function but not
used, tie RI2# high.
GPIO11+IRQ15
DCD2#
AG4
C28
I
Data Carrier Detected.
When low, indicates
that the data transfer device (e.g., modem) is
ready to establish a communications link.
Note:
If selected as DCD2# function but
not used, tie DCD2# high.
GPIO9+IDE_IOW1#
+SDTEST2
DSR2#
AJ1
B29
I
Data Set Ready.
When low, indicates that
the data transfer device (e.g., modem) is
ready to establish a communications link.
Note:
If selected as DSR2# function but not
used, tie DSR2# low.
GPIO10+
IDE_IORDY1