Omron CS1W-CT021, Operation Manual

Page: 154 / 201

@*'#""&4'+
Section 4-6
$&,
All 4 Digital Inputs are assigned in sequential order to consecutive External Inter-
rupt Tasks starting from Digital Input 0. By defining an Offset you determine the
External Interrupt Task number of the (first) External Interrupt Task that is
assigned to Digital Input 0. The remaining 3 Digital Inputs are assigned to the
respective external interrupt task numbers in increasing order starting from “Offset
+ 1”.
For example, an Offset of 30 means that Digital Input 0 is assigned to External
Interrupt Task Number 30, Digital Input 1 to External Interrupt Task Number 31,
Digital Input 2 to External Interrupt Task Number 32 and Digital Input 3 to External
Interrupt Task Number 33.
Since there are 256 External Interrupt Tasks available (numbered 0 to 255) the
Offset can be maximum 252. With an Offset of 252 the last Digital Input (I3) will be
assigned the last available External Interrupt Task 255 (=252+3).
Note 1. Multiple interrupts generated at the same time will be queued in FIFO-order
inside the High-speed Counter Unit. If the FIFO-buffer is full, i.e. 30 interrupts
are queued, the Unit will generate an error (refer to 5-2-5
"Interrupt FIFO full
error" for more information).
2. If the ranges of external interrupt task numbers that are assigned to the Outputs
and the Digital Inputs overlap, the Unit does not generate an error.
Input External Interrupt
Task Number
0 (=I0) Offset
1 (=I1) 1
2 (=I2) 2
3 (=I3) 3
General Setting:
m+4
Interrupt Task Offset (Inputs):
Set between 000 - 252
(BCD)
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
W902-E2-03.book Seite 139 Donnerstag, 7. Oktober 2004 2:06 14