TouchTalk — Arduino Touch-to-Message Aid

A beginner-friendly Arduino project that turns a button press or touch-sensor input into a short message on a 16×2 LCD. Eight inputs provide six everyday phrases, Repeat, and Clear, with buzzer feedback.

No Arduino? You can run the project in your browser using Wokwi. No physical board, sensors, wiring, or Arduino IDE are needed for the simulation.

Start a new Wokwi project · Watch/download the demo video · Circuit diagram

Preview

Actual Wokwi screenshot extracted from the supplied demonstration video:

Animated demonstration

Open the full demo video — MP4, about 14 seconds

The GIF plays directly in the README. The original MP4 is included in the repository; use the link to open it, or download it if GitHub shows a file page instead of a player. The video is preserved unchanged.

What the project does

• Displays six fixed phrases on an I2C LCD.
• Prints the same messages in Serial Monitor.
• Beeps when a message is selected, with a longer Help beep.
• Repeats the last message or clears it.
• Requires all inputs to be released between actions.
• Rejects multiple inputs detected together.
• Uses short functions, comments and straightforward if / else statements.

This is a fixed-phrase communication prototype, not a sign-language translator or a Braille keyboard. It may be useful for someone who prefers tactile input, including a blind person who also needs communication assistance. Blindness itself does not imply an inability to speak. The LCD is for the communication partner; raised labels help a user locate inputs. The buzzer acknowledges actions but does not speak the selected phrase.

Run without an Arduino — Wokwi

1. Get the files

On GitHub, select Code → Download ZIP, then extract it. If you already have this project ZIP, simply extract it.

2. Create the simulation

Open https://wokwi.com/projects/new/arduino-uno on a computer browser. This is a new-project page, not a saved TouchTalk simulation link.

3. Paste the Arduino code

1. Open the downloaded sketch.ino with Notepad or another text editor.
2. Copy its complete contents.
3. In Wokwi, click the sketch.ino tab.
4. Select all the starter code and replace it with the copied code.

Keep this setting:

const bool useWokwi = true;

4. Load the complete circuit

1. Open the downloaded diagram.json in a text editor and copy all its contents.
2. Click Wokwi's diagram.json tab.
3. Replace the entire existing JSON with the downloaded contents.

The Uno, LCD, buzzer, eight buttons and connecting wires should appear automatically. You do not need to place each part by hand.

5. Add the display library

Open Library Manager, press +, search for LiquidCrystal I2C, and add it. Alternatively, create libraries.txt from the editor's file menu and paste the included file contents:

LiquidCrystal I2C

Wire.h is supplied with the Arduino core; no separate installation is required for it.

6. Start and interact

Click the green ▶ Start simulation button. After startup, the screen shows:

TouchTalk ready
Touch one pad

Click and briefly hold a button, then release it. With the circuit area focused, keyboard keys 1–8 select the same inputs. Hold and release for roughly 0.1 seconds each at normal simulation speed; a slow browser may need longer.

Button / key	Arduino pin	LCD action
1 — YES	D2	Yes
2 — NO	D3	No
3 — WATER	D4	I need water
4 — FOOD	D5	I need food
5 — TOILET	D6	Need the toilet
6 — HELP	D7	Please help me
7 — REPEAT	D8	Repeat the previous message
8 — CLEAR	D9	Forget the previous message and return to ready

Example: choose 3 WATER. The LCD shows My message: / I need water, while Serial Monitor shows:

MESSAGE: I need water

Select 7 REPEAT to send it again. Select 8 CLEAR, then 7 REPEAT: the display shows No message yet.

Wokwi pushbuttons represent the digital outputs of touch modules. This tests the program and simulated circuit, not real capacitive sensitivity. Audio output consists of buzzer tones, not speech.

7. Save your own simulation

Use Wokwi's Save button and follow its current account/privacy prompts. After saving, copy your project URL into this README if you want visitors to open your assembled simulation directly. No permanent Wokwi project URL is included in this package.

How the code works

Code	Purpose
setup()	Initializes the input pins, LCD, Serial Monitor and buzzer once
loop()	Repeatedly checks inputs and selects an action
readButtons()	Returns 0 for none, 1–8 for one input, or −1 for multiple inputs
showOnDisplay()	Prints two lines on the LCD
sendMessage()	Remembers and displays the phrase, logs it and beeps
lastMessage	Stores the phrase used by Repeat
waitingForRelease	Prevents a held input from repeatedly sending
delay(40)	Separates two readings for a simple debounce check

To follow the Water example: readButtons() returns 3, loop() enters else if (button == 3), and sendMessage("I need water") updates the outputs.

The debounce method is intentionally simple and blocking: it compares two readings 40 ms apart. It does not prove the signal was stable throughout that interval. Very short presses can be ignored; an action already sent cannot be undone by a later second touch.

Build with real hardware

You need an Arduino Uno, eight active-HIGH momentary TTP223 touch modules, a 16×2 LCD with I2C backpack, a small low-current passive piezo buzzer, breadboard, jumper wires and a USB cable.

Part connection	Destination
Touch-module OUT pins 1–8	D2–D9 respectively
All touch-module VCC pins	5V
All touch-module GND pins	GND
LCD VCC / GND	5V / GND
LCD SDA / SCL	A4 / A5
Piezo + / −	D12 / GND

1. Disconnect power before wiring. Follow each module's printed pin labels; physical pin order varies.
2. Verify the sensors output LOW at rest and HIGH while touched. Use momentary mode, not toggle mode.
3. Change const bool useWokwi = true; to const bool useWokwi = false;.
4. For Arduino IDE, create a separate folder named TouchTalk, copy sketch.ino into it as TouchTalk.ino, and open that file. Keep only one .ino copy in that folder.
5. Install LiquidCrystal I2C by Frank de Brabander, choose Arduino Uno and the connected board's port, then upload.
6. Leave sensors untouched while powering on so they can calibrate.

For physical pushbuttons wired to GND instead of touch modules, keep useWokwi = true; that mode also works with real active-low buttons.

Choose raised labels or Braille labels with the intended user. Place labels beside active touch areas, add a clear orientation marker, and leave enough space between pads. Touch sends immediately after the simple debounce check; there is no preview/confirm stage. Actual usability and accidental activation need testing with the user.

This beginner version contains no DFPlayer, MP3 playback, speech recognition or text-to-speech. HELP only displays a local message and beeps; it does not call or alert anyone remotely. It is not a sole emergency communication system and does not provide tactile output for deafblind users.

Troubleshooting

Problem	Check
LiquidCrystal_I2C.h: No such file	Add LiquidCrystal I2C in Library Manager
Only an Uno appears	Replace the complete diagram.json, not only sketch.ino
A quick click does nothing	Hold longer, then release all inputs; wait for startup to finish
Simulation is slow	Watch simulated time; Ctrl-click (Cmd-click on macOS) can hold a button, and another click releases it
Circuit is outside the visible area	Use the circuit menu's Fit option
LCD is blank on hardware	Check power, contrast, SDA/SCL and the backpack's I2C address; code uses 0x27
Touch sensor response is reversed	Check useWokwi = false and active-HIGH momentary module configuration
No spoken words	Expected: this version only produces tones
Wokwi rejects an uploaded file	Starter filenames already exist; replace their text instead

Files

File	Purpose
sketch.ino	Beginner-friendly Arduino program
diagram.json	Complete Wokwi circuit
libraries.txt	Display-library dependency
assets/wokwi-preview.png	Screenshot from the supplied demo
assets/wokwi-demo.gif	README animation derived from the demo
assets/wokwi-demo.mp4	Original supplied video, unchanged
assets/circuit-diagram.png	Pin-level wiring diagram for this version
docs/GITHUB_SETUP.md	Publishing instructions
docs/TESTING.md	Evidence, checks and limitations

Validation

The supplied video shows the beginner sketch running in Wokwi with phrase output in Serial Monitor. The preview is extracted from that recording. See testing notes for separately checked code behavior and remaining physical-hardware checks.

References

• Wokwi button reference
• Wokwi I2C LCD reference
• Wokwi diagram format

Author

Ankit Kumar Panda