Signal Utilities

Small stateless surfaces that do not own a peripheral: the bit-bang shift functions and the random generator.

For a square wave on a buzzer, a PWM channel at 50% duty does it in two calls — setPeriod(1_000_000_000 / hz) then setDuty(0.5); see Analog & PWM.

Shift Registers (Bit-Banging)

Two module functions — a bounded sequence of pin toggles, not a class:

import { shiftOut, shiftIn } from '@typecad/hal';

shiftOut(dataPin, clockPin, 0b10110001);        // MSB-first by default
const b = shiftIn(dataPin, clockPin);           // reads 8 bits

Random Numbers

import { Random } from '@typecad/hal';

Random.seed(0xC0FFEE);               // only when you want reproducibility
const die = Random.upTo(6);          // 0–5
const pct = Random.between(1, 101);  // 1–100
const big = Random.int();            // non-negative 31-bit integer

On Zephyr the generator is seeded from hardware entropy at boot, so seed() is only needed for deterministic sequences (tests, simulations).

API Reference