•
FLAG
4-9
connect to the LEDs and supply feedback for program execution. For
example the user can write code to trigger a flag (and the corresponding LED)
when a routine is complete the LED will light. The LED flags are configured
through the IOCTL register and are set/read through the IOSTAT register.
•
FLAG
10
is available to the EMAFE interface and is used for signaling. The
EMAFE flag is configured through the IOCTL register and is set/read through
the IOSTAT register.
•
FLAG
11
is reserved for the monitor to determine if the AD1819 codec is
enabled. When using the monitor program supplied with the EZ-KIT Lite
board, do not use or alter this flag pin.
Table 3-1 Flag Summary
Flag
Use
Flag
0-3
Push-button
Input
(SW3, SW5, SW7, SW8)
Flag
4-9
LED
Feedback
Flag
10
EMAFE
Flag
Flag
11
Reserved for monitor
3.2.1.2 Interrupts
Each of the three external interrupts, IRQ
0-2
, of the ADSP-21065L are directly accessible
through push button switches SW2, SW4, and SW6 on the EZ-KIT Lite board. IRQ
0-1
are “wire-Or’ed”; IRQ
0
is used to implement interrupt driven serial routines with the
UART and IRQ
1
is provided for use with an EMAFE board and can be set to read and
write registers.
The external interrupts are controlled through the MODE1, MODE2, and IMASK regis-
ters and are configured in one of two ways: by modifying the vector table or through
instructions in user code. The MODE2 register also controls the interrupt sensitivity
between level and edge. To prevent an interrupt from being masked, write to the
particular interrupt in the IMASK register.
The monitor program running on the ADSP-21065L uses three interrupts; IRQ0, SPT1I
and SFT3, for normal operation. These interrupt vectors are provided in the
“demorth.asm” file that comes with the EZ-KIT Lite.
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