Specifications

UART Controller
16-8 Copyright © 2004, 2006 ARM Limited. All rights reserved. ARM DDI 0287B
16.3 UART signals on pads
The signals connected to pads are listed in Table 16-1.
Table 16-1 Pad signal descriptions
Name Direction Description
nUART0CTS
nUART1CTS
nUART2CTS
Input UART Clear To Send modem status signal, active LOW.
The condition of this signal can be read from the UARTFR
register.
nUART0DCD Input UART Data Carrier Detect modem status signal, active
LOW. The condition of this signal can be read from the
UARTFR register. (nUARTDCD is tied HIGH on
UART1 and UART2.)
nUART0DSR Input UART Data Set Ready modem status signal, active LOW.
The condition of this signal can be read from the UARTFR
register. (nUARTDSR is tied HIGH on UART1 and
UART2.)
nUART0RI Input UART Ring Indicator modem status signal, active LOW.
The condition of this signal can be read from the UARTFR
register. (RI is tied HIGH on UART1 and UART2.)
SIRIN0 Input SIR Received Serial Data Input.
In the idle state, the signal remains in the marking state 1.
When a light pulse is received which represents a logic 0,
this signal is a 0.
(SIRIN is tied LOW on UART1 and UART2.)
UART0RXD
UART1RXD
UART2RXD
Input UART Received Serial Data signal.
UARTCLKEXT Input External clock reference for peripheral. This signal can be
selected instead of the internal clock reference.
nSIROUT0 Output SIR Transmitted Serial Data Output, active LOW. In the
idle state, this signal remains 0 (the marking state). When
this signal is set to 1, an infrared light pulse is generated
which represents a logic 0 (spacing state).
(SIROUT is not used on UART1 and UART2.)