Timer And Interrupts - Beckhoff C1120 Technical Documentation Manual

C1120 S5 to II/O Lightbus Interface Beckhoff II/O-Lightbus System

Timer and Interrupts

With this menu the four fast interrupts of the Beckhoff II/O-Lightbus System can be
configured:
It is possible to connect the interrupts with a free running timer. To select the timer period,
enter the timer period in the equivalent field. Valid values are 0 ms (meaning "timer
disabled") up to 1677 ms.
Interrupts can be counted: The field "count address" holds the base address of the counters of
the four interrupts. Each counter is two bytes long, therefore 8 bytes are reserved. To enable a
counter, the field "Count" should hold a "1".
The fast interrupts are configured by moving the cursor the the equivalent line and interrupt
field, pressing key "F6" repetitively to choose the characteristic from "not activated", "rising
edge", "negative edge", "toggle".
The fast interrupts are configured by positioning the cursor on the relevant interrupt field and
pressing the function key F6 to select the desired characteristic. Pressing the F6 key toggles
between the options " Not Activated" , " Positive Edge" , " Negative Edge" and " Change of
Edge" .
If the relevant interrupt channel is activated by a " 1" in the column " S5 IRQ" , when the
interrupt event occurs, an interrupt is triggered on the S5.
An interrupt request is reset by reading a specific cell in the Dual Port RAM. The base address
entered in the field S5 IRQ Address indicates the address offset. In the example, accessing
the address 190 would reset interrupt request 0, and accessing address 192 would reset
interrupt request 2.
Date 27.06.97 Version 2.1 Page 19 of 52