01 · Introduction

What Is the P-Bit?

The P-Bit is a mini environmental computer. You connect it, turn it on, and it starts measuring what's happening around you: air temperature, how much humidity there is, whether there's a lot or a little light, the noise level, whether a plant's soil is dry, and even the temperature of a probe you can dip into water or soil.

It has a colour screen, an LED that changes colour depending on what it detects, and a beep that warns you when something goes outside the range you configure. Everything is controlled with a single wheel: the encoder.

Input

The 6 Sensors

Measures air Temperature and Humidity (DHT11), Light, ambient Sound, Soil moisture, and liquid Temperature (DS18B20).

Communication

LED / Screen / Sound

Colour LCD screen, status RGB LED, and an internal buzzer for sound alerts plus Bluetooth (BLE) connectivity.

P-BIT SYSTEM

STARTING...

Use the buttons to navigate the simulator.

02 · Getting Started

First Power-On

Your first minute with the P-Bit is very simple.

Connect: Power it via USB-C. The screen turns on immediately.
Choose the language: Turn the wheel to choose between Spanish, Catalan, or English.
Confirm: Press the wheel to confirm. Done! The P-Bit will remember this forever, even if you turn it off.

03 · Controls

The Encoder: Everything in One Button

A single rotary wheel is your entire control. It has three gestures:

Turn	Switch screens, move through menus, and adjust numeric values.
Short press	Confirm a selection or trigger a quick action (like pausing the timer).
Long press (~1.2s)	Open the settings menu for the current screen.

General rule: Turn = move. Short press = confirm. Long press = open menu.

04 · Navigation

The Screen Flow

Turn the encoder to cycle through the screens. The order is always the same:

🌡️ Temperature → 💧 Humidity → ☀️ Light → 🔊 Sound → 🌱 Soil → 🌊 DS18B20 → ⚙️ System → ⏱️ Timer → 📈 Graph

Quick actions (without opening a menu)

Screen	What the short press does
Temperature / DS18B20	Instantly switches the display unit between °C and °F.
System	Turns the buzzer on or off (Sound ON ↔ OFF).
Timer	Starts or pauses the countdown.
Graph	Switches the variable being plotted (Temp ↔ Hum).

05 · Menus

How to Configure

Most screens have a menu. The flow is always the same:

Press and hold for ~1.2 seconds to open the menu.
Turn to choose an option and press to confirm.
If you're editing a numeric value, turn to change it and press to move to the next digit or confirm.
You'll see "SAVED" in green. Press once more to return to the menu, and choose "Exit" to go back to reading mode.

Important: While a menu is open, the P-Bit won't go to sleep automatically or send data over Bluetooth. Exit the menu when you're done.

06 · The Sensors

🌡️ Air Temperature

Measures ambient heat with a tank-style visual that changes colour: blue when it's cold, green when optimal, red when it's hot.

SENSOR
DHT11 / SHT20

OPERATING RANGE
0°C to +50°C

ACCURACY
± 1°C / ± 0.3°C

REFRESH RATE
2 Hz (500ms)

Interactive Threshold Simulator

24.0°C OPTIMAL

TEMP MENU

> LIMITS: Set the minimum and maximum threshold (e.g. Min: 18°C, Max: 26°C). If the temperature goes outside this range, the screen will turn blue or red.
> UNIT °C / °F: Toggles between Celsius and Fahrenheit. Note: Changing this also affects the DS18B20 probe, since they share the global setting.
> ALERTS ON/OFF: Lets the P-Bit beep and flash red globally if the temperature goes outside your limits.
> RESET: Restores the limits to factory values.
> BACK: Returns to the reading screen.

Classroom Experiment: Set a maximum limit of 24°C and take the P-Bit out to the sunny courtyard and then into the shade. Time how many seconds it takes for the temperature to jump and trigger the acoustic alarm.

Keep in mind that the internal sensor can heat up slightly from internal dissipation if the device has been on for a long time or is plugged into USB. For ultra-precise readings in direct contact, use the external DS18B20 probe.

07 · The Sensors

💧 Air Humidity

Shows how much humidity is in the air with a horizontal bar. You can define what counts as "Dry" and what counts as "Very Humid".

SENSOR
DHT11 / SHT20

OPERATING RANGE
20% to 90% RH

ACCURACY
± 5% RH

RESOLUTION
1% RH

Interactive Humidity Simulator

30%

60%

48% RH

NORMAL

💧

Usage tip: Don't bring your hand or mouth close to the sensor if you want a stable reading — a single breath will spike the measurement to +80%. It's a great sensor for installing in terrariums or simulating a school greenhouse's climate.

08 · The Sensors

☀️ Ambient Light

Measures light and automatically classifies it: Dark, Dim, Indoor, Bright, or Sunlight.

SENSOR
Analog LDR / BH1750

LUX RANGE
0 to 65,535 Lux

SPECTRUM
Visible (similar to the human eye)

Ambient Lux Simulator

420 Lux

INDOOR

💡

DARKDIMINDOORBRIGHTSUNLIGHT

LIGHT MENU

> LUX LIMITS: Set the light threshold you consider acceptable (e.g. Minimum 300 lux for a study classroom, Maximum 2000 lux).
> VISUAL MODE: Switch between ABSOLUTE (real Lux), LOGARITHMIC % (0-100% visual scale), or RAW ADC (for electronic analysis).
> ALERTS ON/OFF: Beeps if there's too little or too much light.
> RESET: Restores the factory light settings.
> BACK: Returns.

You can calibrate the lux thresholds from the menu to adapt them to your classroom or the outdoors. By switching the Visual Mode, you can use the sensor as a photographic tool (Absolute) or a pure engineering one (Raw ADC).

Automatic LED: The P-Bit's main RGB LED turns off automatically when you enter this screen. This prevents the device's own coloured light from contaminating the light sensor's reading.

09 · The Sensors

🎤 Ambient Sound

Measures the noise level picked up by the built-in microphone, shown as a VU Meter (intensity percentage).

SENSOR
Electret Microphone / INMP441

FREQ. RANGE
20Hz - 20kHz

PROCESSING
RMS over a 50ms window

Interactive VU Meter

15%

SILENT

🤫

SOUND MENU

> HIGH LIMIT (%): Sets the percentage above which noise is considered excessive. Above this, the bar turns RED.
> LOW LIMIT (%): Sets the background noise threshold (Silence).
> ALERTS ON/OFF: Essential if you want the P-Bit to act as a "noise watchdog" in class. If the classroom goes above the high limit, the P-Bit will beep and flash.
> RESET: Restores the noise thresholds.
> BACK: Returns.

Classroom Noise Traffic Light: Turn on Alerts, lower the High limit to 40%, and leave the P-Bit on the teacher's desk. If students get too loud working in groups, the device will warn them automatically.

10 · The Sensors

🌱 Soil Moisture (J6 Port)

External capacitive probe. It doesn't corrode on contact with water and measures soil or pot moisture reliably.

TYPE
Capacitive Probe V1.2

CONNECTOR
JST XH 3-Pin (Yellow J6)

LIFESPAN
> 5 years in moist soil

Watering Simulator

🌱

RAW ADC

2250

45%

OPTIMAL

No watering needed

SOIL MENU

> LIMITS: Set the minimum threshold (soil too dry, needs watering) and maximum (overwatering).
> CALIBRATE 0% (DRY): Clean the probe, hold it in open air, and press here. The system will record the current RAW reading as the new 0%.
> CALIBRATE 100% (WATER): Dip the probe in a glass of water up to the upper white line and press here. It will be recorded as the new 100%.
> ALERTS ON/OFF: Warns you if the plant urgently needs watering (drops below the minimum).
> BACK: Returns.

Why do you need to calibrate? Every type of soil or substrate has a different density. The two-point calibration process (0% and 100%) ensures the percentage bar is fully accurate for your specific experiment.

Hardware care: Remember that the electronics at the top of the probe (where the wires are) are NOT submersible. Sink the probe into the soil only up to the white dividing line.

11 · The Sensors

🧊 DS18B20 Probe (External Temp.)

Waterproof stainless-steel probe (black cable). Used to measure temperature in liquids, deep soil, or ice.

PROBE TYPE
Digital One-Wire

MEASUREMENT RANGE
-55°C to +125°C

PROTECTION
IP67 (Submersible)

External Probe Simulator

🌡️

LIQUID

18.2°C

NORMAL

One-Wire reading OK

Thermal Comparison: With the internal DHT sensor and the DS18B20 probe running at the same time, students can design experiments that measure the thermal differential: why is the soil in the sun at 35°C if the courtyard air reads 25°C?

12 · Operating System

⚙️ System and Sleep (ZZZ)

Manages the device's overall behaviour and power saving.

Power Management Simulator

Set how long the P-Bit stays idle before entering power-saving mode.

STATUS: SYSTEM ACTIVE

☀️

ZZZ

Battery savings +0%

In this menu you can also adjust the screen brightness, turn off Bluetooth (BLE), and check the operating Firmware version (pbit-os).

13 · Operating System

                            05:00
                        

Mode: Lab / Demo

14 · Operating System

Trend Monitor

MAX

MIN

INTERVAL: 2 SEC/POINT

DATA: 15 PTS

15 · Operating System

🔔 Global Alert System

Critical Alarm Simulator

Press to see how the P-Bit reacts when a threshold is exceeded.

RGB LED

🔕

🔔

SCREEN

SYSTEM NOMINAL

This happens even if you're on the Light or System screen. The P-Bit is always measuring everything in the background.

16 · Hardware

Hardware, Ports & Logic

The P-Bit is built with a Maker philosophy. It's fully transparent.

USB-C Port

Power only (5V DC). No serial data transfer, to prevent accidental resets in the classroom.

I2C Bus (Blue)

Expansion ports for smart sensors. Industry-standard protocol for maximum compatibility.

J6 Port (Yellow)

High-precision analog input dedicated to the capacitive soil moisture probe.

Bluetooth BLE

Broadcasts data at 1Hz. Native connection with P-Blocks, Data Dashboard, and PowarED.

Hard Reset

Physical rear button. Restarts the operating system without affecting settings or calibrations.