dSPACE CLP1104, Hardware Installation And Configuration

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Signal Connection to External Devices
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DS1104 Hardware Installation and Configuration March 2004
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Changing Power-up Default
After power-up the bit I/O unit is configured to input mode. In this
case, the I/O pins have a defined logical high level because of the built-
in pull-up resistors.
If you want to change the power-up default, you can set the I/O pins
to a defined logical low level by connecting a 1 k
Ω
pull-down resistor
from ground to each I/O pin.
Recognizing User Interrupts
IO16 ... IO19 can be used as external interrupt inputs. To allow the
interrupt controller to recognize incoming user interrupts, the input of
the interrupts must be kept high for at least 1
µ
s. The interrupt is
activated by the high to low transition of the signal. The signal must
remain low for at least 100 ns after the transition.
high
low
t
T
high
T
low
T
high min
: 1
µ
s
T
low min
: 100 ns