FP-DIO-550 and cFP-DIO-550
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The following table shows the four pattern match modes.
Table 4.
Pattern Match Modes and How They Affect Channel Behavior
To specify the input pattern you want to detect, you must enter the
pattern mask and pattern value in MAX. The mask identifies the
input channels included in the pattern, and the value specifies
which state the inputs must be in for a positive match. The mask
and the value are eight-bit binary numbers, and you must convert
them to decimal before entering them in MAX. The eight bits
correspond to the eight input channels. A 1 in bit position
n
in the
mask means that input channel
n
is part of the pattern. A 0 in bit
position
n
in the mask means that the channel is not part of the
pattern. A 1 in bit position
n
in the pattern value means that input
channel
n
must be on for a successful match. A 0 in bit position
n
in the pattern value means that input channel
n
must be off for a
successful match.
For example, suppose you want output channel 2 to turn on when
the following condition is true and turn off when the condition is
not true: Input channel 7 is on, 5 is off, 2 is on, and 1 is off. The
other input channels do not matter in this pattern. The following
table shows the bits in this pattern mask.
Pattern Match Mode
Behavior
Set High During Match
The output turns on when the input
pattern is detected and turns off when the
pattern is not detected.
Set Low During Match
The output turns off when the input
pattern is detected and turns on when the
pattern is not detected.
Latch High On Match
The output latches on when the input
pattern is detected. The output stays on
until it is cleared from software at which
point it turns off until the input pattern is
present again.
Latch Low On Match
The output latches off when the input
pattern is detected. The output stays off
until it is cleared from software at which
point it turns on until the input pattern is
present again.
Channel
7
6
5
4
3
2
1
0
Bit
1
0
1
0
0
1
1
0
Conversion
×
128
×
64
×
32
×
16
×
8
×
4
×
2
×
1
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