Analog Devices ADSP-21160 EZ-KIT Lite, Руководство пользователя

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ADSP-21160 EZ-KIT Lite Evaluation System Manual 1-9
Using ADSP-21160 EZ-KIT Lite
Flag Pins
The ADSP-21160 processor holds four general-purpose programmable
flag pins. The flag pins can be used as inputs or output depending on how
they are configured in the
MODE2
system register. The state of a flag can be
written to and read from the
FLAGS
system registers. When the flag pins
are input, their current state can be found by reading the
FLAGS
system
register. Flag pins set as outputs are driven to the value written to the
FLAGS
system register.
The locations of the signals can be found in “ADSP-21160 EZ-KIT Lite
Schematic” on page B-1 . The flag pins are summarized in Table 1-2 . For
more information on flags, refer to the ADSP-21160 SHARC Processor
Hardware Reference
Interrupt Pins
The ADSP-21160 processor holds three interrupt request (
~IRQ
) pins that
let you interact with the running program. The
~IRQ
pins can be used only
as inputs. To use the pins, enable the specific IRQ, as well as enable the
global interrupts. You also need to write a special interrupt service routine
to handle the interrupts when they occur.
Table 1-2. Flag Pin Summary
Flag
1
Pin
1
FLAG3–0
are available on connector
P2
.
Connects To Description
FLAG0 LED3 FLAG2–0
connect to the LEDs. These can be
used, for example, to light a LED when a rou-
tine completes.
FLAG1 LED2
FLAG2 LED1
FLAG3
AD1881A
RESET FLAG3
connects directly to the reset pin of the
AD1881A audio codec. To reset the AD1881A,
drive this signal low.
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