Contec AD12-16(PCI), User Manual

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Functions and Operating Procedures
AD12-64(PCI), AD12-16(PCI)
47
External trigger
An interrupt request signal can be generated by a falling edge of an
external TTL-level signal. Even if it is not specified as an
interrupt source, feeding the status enables monitoring of the
operation. An external trigger is allowed to enable and disable
inputting of external signal by opening and closing an external
trigger gate. Initial status of the external trigger gate is "closed."
"Open" the external trigger gate when using an external trigger.
The following are the control ports for opening an external trigger
gate:
The following are the control ports for closing an external trigger
gate:
The following are examples of timer period settings described in
high-level languages:
Microsoft C Microsoft QBASIC
outp( ADR+8, 8 ); OUT ADR+8 8
: :
outp( ADR+8, 9 ); OUT ADR+8 9
Reference
Sample software : EXTI.C, EXTI98.C
+8
(+08h)
Command
Input D 7 D 6 D 5 D 4 D 3 D 2 D 1 D 0
1 0 0 0 0 0 0 0
+8
(+08h)
Command
Output
D 7
D 6
D 5 D 4 D 3 D 2 D 1 D 0
1 0 0 0 0 0 0 1