ESP32-S3 board
The brain that runs your uploaded sketch.
01 First, know the pieces
What you need
Nothing new to buy — this is the exact circuit you built on Day 4. If it's still wired up, you only need to upload a new sketch. Tap Define on anything you'd like refreshed.
GPIO extension board
Spreads the pins into rows you can reach and label.
LED
The lamp — same LED, same one-way rule as Day 4.
220 Ω resistor
Still in series with the LED, keeping the current gentle.
2 × 10 kΩ resistors
Hold the button's pin steady between presses.
Push button
The same switch — now it toggles instead of holds.
Jumper wires
Temporary, solder-free connections.
Arduino IDE
Uploads the new lamp sketch to the board.
02 Make the physical circuit
Chart the circuit
This is the Day 4 circuit, unchanged — the same chart, so the same chart applies. Click it to enlarge, or skip straight to the sketch if your circuit is still assembled.
LED long leg (+)
→GPIO 2 via 220 Ω
This pin switches the LED on and off.
LED short leg (−)
→GND
Completes the LED's path back to zero volts.
Push button
→GPIO 13
The board reads this pin to catch each press.
10 kΩ resistor
→3.3V
Holds GPIO 13 HIGH until a press pulls it LOW.
Same circuit, same care. Nothing moves on the breadboard today. If you do rewire, keep the LED's long leg toward GPIO 2 through the 220 Ω resistor, and unplug USB first.
03 One action at a time
Build it
Mostly upload-and-watch — the wiring is yesterday's. Tap each step as you go to keep your place.
0 / 6 done
Confirm the Day 4 circuit is still wired, or rebuild it from the chart.
Keep USB unplugged until every wire matches the chart.
Open
Sketch_02.2_TableLamp.inoin Arduino IDE.Upload it to the ESP32-S3.
Press the button once and let go — the LED should latch on.
Press once more — it should turn off.
04 Read just enough code
Read the code
The circuit is the same; the loop is what changed. It now remembers the LED's state, waits out the switch's chatter, and flips only on a clean press. Switch to MicroPython to see the same idea in Python.
void loop() {
if (digitalRead(PIN_BUTTON) == LOW) {
delay(20); // wait out the chatter
if (digitalRead(PIN_BUTTON) == LOW) {
reverseGPIO(PIN_LED); // clean press -> flip the LED
}
while (digitalRead(PIN_BUTTON) == LOW); // hold here until release
}
}
void reverseGPIO(int pin) {
digitalWrite(pin, !digitalRead(pin));
}delay(20)The debounce pause — long enough for the switch's chatter to settle. reverseGPIO(PIN_LED)Flips the LED to the opposite of whatever it is now — on becomes off, off becomes on. while (digitalRead(PIN_BUTTON) == LOW);Waits right here until you let go, so one press can't count twice. Optional side path · same circuit
def reverseGPIO():
led.value(0 if led.value() else 1)
if not button.value():
time.sleep_ms(20)
if not button.value():
reverseGPIO()
while not button.value():
time.sleep_ms(20)time.sleep_ms(20)The same 20 ms debounce pause, written in Python.while not button.value()Holds until you release, so the press registers once.Same pins, same wiring, same behaviour. Run it in Thonny if MicroPython is set up; otherwise skip it — it should never block the Arduino-first path.
05 Understand, don't memorise
Memory and debounce
Two small ideas turn a button into a lamp: the code remembers the light's state, and it refuses to trust a press until the switch has stopped bouncing.
A press starts
The loop sees GPIO 13 go LOW and pauses briefly.
Check again
If it is still LOW after the pause the press was real.
Toggle the LED
reverseGPIO sets the LED to the opposite of what it was.
Until release
The code holds until you let go so one press counts once.
The model
one clean press → flip the remembered state → the lamp stays
Why the LED bounced before
A switch chatters for a few milliseconds as it closes. Without the pause the board would toggle many times per press.
What toggling really is
Instead of following the button live, the code keeps a state and inverts it — that memory is the whole difference from Day 4.
06 Know it worked
Test & debug
Nothing prints today — the proof is whether the lamp stays without your finger.
What you should see
- Press once and release — the LED latches on and stays on.
- Press once more — it turns off and stays off.
- Each full press flips the light exactly once, cleanly.
If a single press sometimes flips twice, the debounce pause is doing its job when it's present — and failing when it's removed.
If it doesn't
- One press flips it twice? Confirm the debounce delay and the wait-until-release line are both present.
- Nothing latches? Re-run Day 4's checks — LED direction, the resistors, GPIO 2 and 13.
- LED flickers while held? You may be on the Day 4 sketch — upload Sketch_02.2_TableLamp.
- Upload fails? Swap in a data-capable USB cable.
07 Make the idea yours
Try this: change how the lamp feels
Same working lamp, one deliberate change to its behaviour. Pick one and note what changed — it fits inside today's 30 minutes.
Tune the debounce
Try delay(5) and then delay(80). Find where presses feel crisp without ever double-flipping.
Name the interaction
In one sentence, describe how this lamp should feel to use — then judge whether your timing delivers it.
Logbook
08 Learn it with a hand on the tiller
Coach me through it
Every lesson ships with a code and a machine-readable packet, so an agent can guide you with full context.
Lesson code
TSK-DAY05-LAMP
Context packet
How the agent should behave: keep it to upload-and-watch on the existing circuit, explain debounce and toggle on request, and check wiring, board, port, and USB before changing code.