Appendix B: Function Block Reference

AutoCore provides standard function blocks inspired by IEC 61131-3. Import them from autocore_std::fb.

RTrig — Rising Edge Detector

Detects false to true transitions. Equivalent to R_TRIG in IEC 61131-3.

#![allow(unused)]
fn main() {
use autocore_std::fb::RTrig;

let mut trig = RTrig::new();

trig.call(false);  // returns false
trig.call(true);   // returns true  (rising edge detected)
trig.call(true);   // returns false (no transition)
trig.call(false);  // returns false
trig.call(true);   // returns true  (another rising edge)
}

FTrig — Falling Edge Detector

Detects true to false transitions. Equivalent to F_TRIG in IEC 61131-3.

#![allow(unused)]
fn main() {
use autocore_std::fb::FTrig;

let mut trig = FTrig::new();

trig.call(true);   // returns false
trig.call(false);  // returns true  (falling edge detected)
trig.call(false);  // returns false (no transition)
trig.call(true);   // returns false
trig.call(false);  // returns true  (another falling edge)
}

Ton — Timer On Delay

Output becomes true after input has been true for the specified duration. Equivalent to TON in IEC 61131-3.

#![allow(unused)]
fn main() {
use autocore_std::fb::Ton;
use std::time::Duration;

let mut timer = Ton::new();

// In process_tick:
let done = timer.call(input_signal, Duration::from_secs(5));
// done = true after input_signal has been true for 5 seconds continuously
// timer.et = elapsed time
// timer.q = same as the return value (done)

// If input_signal becomes false at any time, the timer resets
}

Fields:

BitResetOnDelay — Auto-Reset Timer

Sets output to false after a delay. Useful for pulse outputs.

#![allow(unused)]
fn main() {
use autocore_std::fb::BitResetOnDelay;
use std::time::Duration;

let mut reset = BitResetOnDelay::new(Duration::from_millis(500));

// When you set the bit to true, it automatically resets to false after 500ms
reset.set(); // Output becomes true
// ... 500ms later, in process_tick ...
reset.call(); // Call every cycle to update
// reset.q becomes false after the delay
}

RunningAverage — Online Averaging

Computes a running average of values.

#![allow(unused)]
fn main() {
use autocore_std::fb::RunningAverage;

let mut avg = RunningAverage::new();

avg.add(10.0);
avg.add(20.0);
avg.add(30.0);
let mean = avg.average(); // 20.0
let count = avg.count();  // 3

avg.reset(); // Start over
}