Three-Floor Elevator Controller

On an Arduino Nano 33 BLE, control a small three-floor lift: remember floor calls, keep the car's direction and stop at called floors on the way, time the travel and the door, and drive the indicator panel lamps correctly.

Board: Nano 33 BLE · Arduino
Difficulty: Hard
Topic: Timing & Program Flow
Access: Full plan

Solve free (Pioneer challenge)

The task

Three-Floor Elevator Controller A shop on three floors installs a small goods lift. Staff call it with one button per floor. A naive controller serves calls in the order they were pressed and makes the car shuttle past floors where someone is waiting. This one must work like a real lift: keep going in its direction and stop on the way. Times are shortened for the bench, and this is a programming exercise on an emulated board, not a certified lift controller. Hardware Arduino Nano 33 BLE (nRF52840, 3.3 V logic). Serial console on Serial1 (D0/D1), 115200 baud. Serial is USB and is not seen by the tests. Call buttons for floors 1, 2, 3 on D2, D3, D5, each to GND. Use the internal pull-ups (LOW = pressed). A press counts once, after 20 ms without a break, however long the button is held. Lift indicator panel (lamps with resistors on board, HIGH = on): floor lamps F1 on D4, F2 on D6, F3 on D8; UP arrow on D9, DOWN arrow on D10; DOOR lamp (door open) on D11 . The car takes 500 ms to move one floor. The door stays open for 700 ms . Write the sketch in sketch/sketch.ino . In setup() open Serial1 at 115200 baud, set up the pins and the start-up lamps, then print READY . Never block with delay() : calls can come at any moment.

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What you get

Your firmware is built and run on an emulated board and checked by hardware-level tests.
A written walkthrough of the solution.
No development board or local toolchain needed.

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