Signal Connection to External Devices
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DS1104 Hardware Installation and Configuration March 2004
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Notes and Tips on Signal Conditioning
The following notes and tips are intended to help you achieve
optimum results using the incremental encoder interface:
■ Recognizing Encoder Index Interrupts: see below
■ Connecting Encoders on page 133
■ Supplying Power to Encoders on page 135
■ Noise, crosstalk and inductive effects can degrade the signal and
lead to incorrect results if you do not provide correct shielding. For
details refer to Shielding on page 150.
Recognizing Encoder Index Interrupts
To allow the interrupt controller to recognize incoming index interrupts
(IDX1, IDX2), the input of the index interrupts must be kept low for at
least 1 µs. The interrupt is activated by the low to high transition of
the signal. The signal must remain high for at least 100 ns after the
transition from low to high.
high
low
t
T
high
T
low
T
high min
:100 ns
T
low min
:1
µ
s