Omron CS1W-CT021, Руководство по эксплуатации

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Section 5-2
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5-2-4 Preset error
A Preset error is generated if a Circular or Linear Counter is preset with an invalid
Preset Value (refer to 3-4
"Digital Input Functions" for more information about pre-
setting). The Preset Value is invalid if it is outside the counting range of the Circu-
lar or Linear Counter.
Clearing Preset error A Preset error can be cleared by resetting or by presetting the Counter that gen-
erated a Preset error, with a valid Preset Value. To reset a Counter refer to 3-6
"Reset Signals" . To preset a Counter refer to 3-4 "Digital Input Functions" .
5-2-5 Interrupt FIFO full error
Every interrupt that you want to use is assigned to an external interrupt task
number (0-255). This number corresponds with the external interrupt task in the
CS1-CPU that is to be executed when the assigned interrupt is activated (refer to
4-6
"Interrupts" ).
Multiple interrupts, generated by the Digital Inputs and/or the Outputs, will be
queued in FIFO-order inside the High-speed Counter Unit, for as long as the cur-
rent active interrupt is not executed. If the FIFO-buffer is full the Unit will report an
error to the CS1-CPU. All interrupts generated by the Unit, after the “Interrupt
FIFO full” error has occurred will be ignored and will not generate additional errors.
Error Code 2 contains the external interrupt task number of the corresponding
interrupt that was excluded from the full FIFO-queue.
Clearing Interrupt FIFO
error If the speed with which the High-speed Counter Unit generates interrupts is higher
than the speed with which the CS1-CPU executes the interrupts, the FIFO-buffer
inside the Unit runs full and the “Interrupt FIFO full” error is generated. The error
can be cleared by issuing the IOWR-instruction with the Error Clear (“EC”) com-
mand (refer to 4-5-3-5
"Error Clear Command" for details).
The error indicates that the load of interrupts on the CS1-CPU is too high. Clearing
the error as mentioned before most probably needs additional measures to be
taken in order to prevent this error from happening in the future:
•
Mask one or more interrupts of the Unit, which caused the error.
•
Mask one or more interrupts of other Units in the system, which are generating
interrupts as well.
•
Reduce the execution time of the assigned External Interrupt Tasks.
Error Code 1 Error Code 2 Error Description
0470 Counter No. Invalid Preset Value The Linear Counter with the Counter No. as
reported in Error Code 2 is preset with an
invalid Preset Value.
Error Code 1 Error Code 2 Error Description
0480 External Interrupt
Task No. Interrupt-FIFO full The interrupt-FIFO inside the High-speed
Counter Unit is full and the interrupt assigned
to
External Interrupt Task could not be
executed.
W902-E2-03.book Seite 148 Donnerstag, 7. Oktober 2004 2:06 14