ADLINK Technology PCI-8254, Руководство пользователя

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198 Motion Control Theory
3. Reset timer continuously
After the watchdog protection mechanism is enabled, the
watchdog mechanism should be reset within timeout period
to rest the timer and retiming from beginning. In case of
timer timeout relevant events are triggered per setting given
by step 1.
Use
APS_wdt_reset_counter () to reset watchdog.
• Example:
void watchdog_example()
{
// This example shows how interrupt functions work.
I32 board_id = 0;
I32 timer_no = 0; // Only timer 0 to be used
I32 time_out = 10; // Time out is 10*100 ms = 1 sec
I32 EventByBit = 0x01; // Action event is defined by bit.
// Bit0: Motor servo off
// Bit1: Digital output off
// Bit2: PWM off
I32 ret = 0; // return code
//Step 1: 姕⭂妰㗪☐妠䘤⼴䘬ḳẞ
ret = APS_wdt_set_action_event( board_id, timer_no, EventByBit );
//Step 2: ┇≽䚳攨䉿ᾅ嬟㨇⇞
ret = APS_wdt_start( board_id, timer_no, time_out );
// ἧ䓐侭䘬 timer 炻 while loop 炻ㆾ侭㗗⎗⚆ㅱ溆
timer(500ms) // 㭷 500ms ⍣慵伖ᶨ㫉妰㗪☐
{
//Step 3: ᶵ攻㕟䘬慵伖妰㗪☐
ret = APS_wdt_reset_counter( board_id, timer_no );
…Do Something
}
}