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System Expansion Options
B-10
Copyright © ARM Limited 2000. All rights reserved.
B.9
GPIO support for expansion
A number of the GPIO pins on the SA-1100 can be used to support additional functions.
These are:
Table B-3 GPIO pins used to support system expansion
Port
Signal
Function
GPIO[24:23]
CPU_GPIO[24:23]
These two pins can be individually configured as inputs or
outputs. They are connected to JP26. CPU_GPIO23 is also
connected to the system expansion connector JP20.
GPIO25
CPU_GPIO25
This pin is connected to a LED, JP40 and JP26. However, when a
distribution panel is connected (to JP40), this signal is a current
sink for two LEDs. The SA-1100 can provide a 1Hz clock on this
pin as an alternate function using a buffered, trimmed 1 Hz signal
from the RTC in the SA-1100.
GPIO26
CPU_RCLK_OUT
This signal is routed to the XCR3128 PLD and JP20 expansion
connector. The SA-1100 can provide a buffered divide-by-two
version of the core clock on this pin as an alternate function. The
clock is currently unused on the SA-1100 and, to save power,
need not be configured by the software. It could be used by the
PLD for high speed state machines or for latching transient data,
but is not used in the first release of the PLD.
GPIO27
CPU_32KHz
This signal is routed to the XCR3128 PLD and JP20 expansion
connector. The SA-1100 can provide a buffered untrimmed
version of the 32.768kHz crystal on this pin as an alternate
function. The clock is currently unused on the SA-1100 and, to
save power, need not be configured by the software. It can be
used by the PLD for slow speed state machines, but is not used in
the first release of the PLD.
GPIO22
CPU_MEMREQ
These signals are routed to the FPGA and to its associated
expansion connector, J26.
GPIO21
CPU_MEMGNT
GPIO1
CPU_GPIO1
This signal is routed to the expansion connector, J26. It can be
used to generate interrupts to the SA-1100 (see Interrupt control
on page 3-12).
Summary of Contents for Prospector P1100
Page 1: ...ARM DUI 0122A Prospector P1100 User Guide ...
Page 4: ...iv Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...
Page 86: ...Hardware Description 3 54 Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...
Page 140: ...Connector reference A 18 Copyright ARM Limited 2000 All rights reserved ARM DUI 0122A ...