Using Programmable Flag Pins - Analog Devices ADSP-21992 EZ-KIT LITE System Manual

Using Programmable Flag Pins

The ADSP-21992 DSP has eight asynchronous Programmable Flag (PF)
I/O pins (
PF7–0
8-15 can also be used as Programmable Flag pins, depending on the configu-
ration of the DSP.
During reset, the flag pins (
which sets the core clock frequency. After the DSP is reset, the flags are config-
ured as inputs. The direction of the flags is configured though the
and are set and read though the
configuring the flag pins, see the ADSP-2199x Mixed Signal DSP Controller
Hardware Reference. Flags and their uses are described in
Table 2-2. Programmable Flag Pin Summary
Flag Connected To
PF0 LED8
PF1 LED9
PF2 LED10
PF3 LED11
– Push button
PF4 SW3
– Push button
PF5 SW2
AD1803 Reset
PF6
AD1885 Reset
PF7
!
All the programmable flags are available on connector
ADSP-21992 EZ-KIT Lite Evaluation System Manual
) that let you interact with the running program. Data pins
) are used to set the multiplication factor,
PF7–0
FLAGC/S
Description
are connected to the LEDs. They supply feedback for
PF3–0
program execution. For instance, you can write your code to
trigger a flag (and the corresponding LED) when a routine is
complete.
are connected to the push buttons on the EZ-KIT
PF5–4
Lite board and are for user input. For instance, you can tell
your program to poll for a flag and when it occurs, do other
operation, such as to jump to another instruction.
is connected to the AD1803 telephony codec reset, and can
PF6
be used to put the chip in reset.
is connected to the AD1885 audio codec reset, and can be
PF7
used to put the chip in reset.
Using the EZ-KIT Lite
register. For more information on
Table
register
DIR
2-2.
.
P9
2-5