Configuration
CP381
Page 4 - 10
© 2002 PEP Modular Computers GmbH
ID 24107, Rev. 01
4.3.5
Latching on Input Events
In addition to the standard event detection described above, there is a latch mode extension.
This mode is used in cases where it is necessary to capture the inputs when one of the defined
events occurs.
4.3.6
Comparing Input Patterns
In addition to the Event Detection Mode it is also possible to detect a complete input pattern
automatically. In this mode the input vector is continuously compared with the content of the
Input Pattern Compare Register. In the case of a match a flag is set within the Input Status Reg-
ister. Single inputs can also be masked out individually in the Input Pattern Mask Register.
Table 4-9: Input Latch-on-Event Register, Bit Map
Bits
Type
Default
Function
31-30
r
0
Not used
29 – 0
r
0
Latch on event, enable bits to activate
Note...
A set bit means that a detected event on the corresponding input is latched. If
all bits are enabled all inputs are latched immediately. To switch back from latch
mode into active mode all detected events and the input latch-on-event status
flag have to be reset by writing "1" to the corrresponding bits in the Input Status
Register.
Table 4-10: Input Pattern Mask Register, Bit Map
Bits
Type
Default
Function
31-30
r/w
0
Not used
29 - 0
r/w
1
Input event mask bits
Note...
A set bit means that the corresponding input is masked out for pattern recogni-
tion. There is no special enable for pattern recognition since it is switched off by
default as long as all mask bits are set.
Table 4-11: Input Pattern Compare Register, Bit Map
Bits
Type
Default
Function
31-30
r/w
0
Not used
29 - 0
r/w
1
Input pattern compare bits
Note...
This register stores the input compare data. A compare match is reported within
the Input Status Register (Bit 31). To reset a compare match, the status flag has
to be reset by writing "1" to it and also the match condition must cease.
