Analog Devices ADSP-21992 EZ-KIT LITE, Системное руководство

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Jumper Settings
3-14 ADSP-21992 EZ-KIT Lite Evaluation System Manual
If
JP2
is in the 2-3 position, the power-on reset (POR) of the
ADSP-21992 is directly connected to the reset pin of the ADSP-21992.
The 1-2 position (default) is the recommended configuration when using
the Vi+ development tools.
Voltage Reference Selection Jumpers (JP3, JP4)
The configuration of two jumpers (
JP3
and
JP4
) is required to control the
selection of the ADSP-21992 DSP’s internal voltage reference or the
external voltage reference provided on the ADSP-21992 EZ-KIT Lite
board. The appropriate settings for the jumpers to select internal or exter-
nal voltage reference operation are:
• Internal reference:
P3
in position 1-2, and
JP4
is open
• External reference:
P3
in position 2-3, and
JP4
is closed
Refer to “Reference Voltage Generation” on page 3-6 for details on volt-
age voltage operation.
PWM Trip Jumper (JP5)
Connecting jumper
JP5
in the 2-3 position ties the
PWMTRIP
pin of the
ADSP-21992 to +3.3V via a 4.7 Kohm resistor and enables the
PWM
out-
puts. In this case, the
PWMTRIP
pin of the ADSP-21992 can be defined by
external circuitry via the
PWM
connector (
P10
). Alternatively, connecting
jumper
JP5
in the 1-2 position connects the
PWMTRIP
pin of the
ADSP-21992 to
GND
, thereby permanently disabling the
PWM
outputs. A
third alternative is to leave
JP5
unconnected. Again, in this case, the pin of
the ADSP-21992 is connected to the
PWM
connector (
P10
) so that its value
can be defined by external circuitry.