Analog Devices ADSP-2189M EZ-KIT Lite, Руководство пользователя

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ADSP-2189M EZ-KIT Lite Evaluation System Manual 2-17
Using EZ-KIT LITE Software
TalkThrough
Demonstrates how to use a circular buffer, which spans five pages of the
ADSP-2198M’s DM overlay memory as input and then sends the data
back out to the
Line Out
of the AD73322 codec. This program is inter-
rupt intensive and performs best at a low baud rate (9600).
Timer
Demonstrates how to hook into the timer interrupt handler. The timer
interrupt generates a 1-second on/off pulse on the
FL1
LED. The idea
behind the timer interrupt is that the monitor program sets a timer at
3 times the baud rate and expects to receive 10 bits
(3 x BAUD x 10 = 1 second). When every counter has expired, the reset
FL1
is executed.
#
You can not set breakpoints in the interrupt routine if using the
ADSP-2189M monitor program
The
TPERIOD
register contains the current period of the timer. It is set to 3
times the baud rate. The timer is used as a baud rate generator so the
smaller the period, the faster the interrupt will occur. It is not advisable to
change the
TPERIOD
register since this will change the monitors baud rate,
and communications is lost with the host.
"
This interrupt will continue to be vectored to even after the pro-
gram has halted.