What Is a Raspberry Pi?

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The Raspberry Pi is a palm-sized single-board computer developed by the Raspberry Pi Foundation in the UK and its subsidiary Raspberry Pi Ltd.
It was born in 2012 as an inexpensive computer for children to learn programming, but today it is widely used not only in education and hobbies but also on the factory floor, in digital signage, embedded industrial equipment and factory data collection.

This page introduces the history of the Raspberry Pi, the models and specs currently available and what it is used for, and finally proposes system configurations for collecting and displaying data connected to a PLC and integrating with PCs and the cloud.

Background and history of the Raspberry Pi

Background

Around 2006, Eben Upton and colleagues at the University of Cambridge Computer Laboratory were concerned that applicants to the computer science course had less programming experience every year.
Children in the 1980s naturally encountered programming on home computers such as the BBC Micro, but as PCs and game consoles became expensive "things you must not break", the environment for casual tinkering had been lost.

So, aiming for "a computer children can freely play with, cheap enough that breaking it doesn't matter", the Raspberry Pi Foundation was established in 2009, and the first product, the "Raspberry Pi Model B", was released on February 29, 2012 for $35.
Orders flooded in right after launch, and as engineers and makers around the world, not just educators, began using it for electronics, servers and embedded devices, it spread to the wide range of uses we see today.

Raspberry Pi timeline

2012-2015: Born as an Educational Computer

The first model had modest performance, but it was popular because it ran Linux and Python and could control LEDs and sensors directly via GPIO. In 2014 the "Compute Module", which turned the board into a module, appeared and opened the way to embedding it in mass-produced products.

2016-2019: Star of the IoT Era

With Wi-Fi/Bluetooth built into the Raspberry Pi 3, it spread rapidly as an IoT device that sends sensor data to networks. The Raspberry Pi 4 added USB 3.0 and Gigabit Ethernet, giving it practical performance as a file server or lightweight desktop PC.

2020s: Expansion into Industry and Microcontrollers

Compute Module 4/5 are embedded in products from industrial equipment manufacturers and are used in airport departure boards, thin client terminals and more. With its own RP2040/RP2350 microcontroller chips, it has also become a major presence in microcontrollers, not just Linux computers.

Models and specs currently available

The main models officially on sale as of October 2026 are introduced in four categories. Raspberry Pi emphasizes long-term supply, and older generations are still in production.

Single-board computers

Keyboard-integrated

* The Raspberry Pi 500+ looks almost the same as the Pi 500 (with a mechanical keyboard), so only the Pi 500 is pictured.

The keyboard-integrated models also expose GPIO on the back, so you can do electronics while using it as a development PC. As a shop-floor terminal, a single-board model in a case is easier to install.

Compute Module (Embedded Modules)

A Compute Module cannot be used alone; it is mounted on a carrier board with I/O and connectors. Many commercial industrial controllers and HMIs contain a Compute Module. Choosing a model with eMMC avoids microSD cards, giving peace of mind on sites where vibration or write endurance is a concern.

Microcontroller Boards (Pico Series)

The Pico is not a computer that runs Linux but a microcontroller board like an Arduino. It runs as soon as power is applied with no OS boot wait, so an effective combination is to let the Pico handle real-time parts such as sensor reading and pulse measurement while a Pi 5 handles aggregation and communication.

About Prices

Since late 2025, due to soaring memory (LPDDR4) prices driven by demand for AI data centers, prices have been raised in stages, mainly for models with more memory. The official recommended retail prices (USD) as of October 2026 are as follows.

Long-term supply

Raspberry Pi has committed to long-term supply: the Raspberry Pi 4 will be produced until at least January 2034, and the Raspberry Pi 5 and Compute Module 5 until at least January 2036. When you plan to embed it in equipment and use it for more than 10 years, this long-term supply policy is very reassuring.

Which Should I Buy? Recommendations by Purpose

What Is It Used For?

Education and programming

In education, its original purpose, it is used worldwide in school programming classes and as teaching material for electronics with Python. The environment can be reset just by swapping the microSD card containing the OS, making it ideal as a learning environment where "breaking it is fine".

Hobbies and home servers

It is popular as a small server that costs little in electricity even when running 24 hours, for file servers, media servers, home automation (Home Assistant, etc.), network ad blocking, retro game consoles and more.

Industrial and embedded use

• Digital signage (information displays in stores, stations and airports)
• Thin client terminals, kiosk terminals
• Inside industrial controllers and HMIs (products with a Compute Module)
• Image inspection and object detection with a camera and AI accelerator (AI HAT+)
• IoT gateways (relaying between on-site equipment and the cloud)

Factory automation (FA)

In factories, the PLC handles control itself, and the Raspberry Pi is often placed "next to" the PLC to collect, show and connect data.

• Collect operating status and production counts from PLCs and record them in a database
• Show operating status and graphs on shop-floor monitors and tablets
• Act as a converter to connect old equipment (such as PLCs with only serial communication) to networks
• Act as a gateway that sends factory data to PCs, higher-level systems and the cloud

Compared with upgrading PLCs or introducing a large SCADA system, the big advantage is that you can start small and add more units once it works. The next section introduces this usage concretely.

Collecting and displaying data connected to a PLC

Division of roles between the PLC and the Raspberry Pi

The key point is not to let the Raspberry Pi do control. If you leave the PLC's existing program untouched (or at most group the data to be read) and have the Raspberry Pi only read the PLC's memory from outside, you can start collecting data without affecting equipment operation.

Basic configuration

One Raspberry Pi handles "collection", "storage" and "display", so no PC needs to run constantly. No dedicated software is needed for display; it can be viewed in the browser of a PC or tablet on the same network.

Connection methods

PLCs from major manufacturers have communication protocols for reading and writing PLC memory over Ethernet. With Python libraries, they are easy to access from a Raspberry Pi.

Sample: Recording KV Series Data in SQLite

A sample reads DM0 to DM3 of a KEYENCE KV series PLC every second and records them in an SQLite database on the Raspberry Pi. It covers everything on one page, from creating a Python virtual environment (venv) to checking the recorded data, so refer to it when trying it on real equipment.

For OMRON (FINS) and Mitsubishi (MC protocol), you can record in the same way just by replacing the reading part with the functions of each library.

Display methods

Proposed Configurations for PC and Cloud Integration

Depending on scale and purpose, we recommend starting from one of the following four configurations. You can start with configuration 1 and expand to configurations 2 to 4 as needed.

import json
import paho.mqtt.client as mqtt       # pip install paho-mqtt

client = mqtt.Client(mqtt.CallbackAPIVersion.VERSION2)
client.tls_set()                      # Always encrypt with TLS when connecting to the cloud
client.connect('broker.example.com', 8883)
client.loop_start()

payload = {'ts': ts, 'line': 'L1', 'plc': 'KV-8000', 'dm': values}
client.publish('factory/line1/plc1', json.dumps(payload), qos=1)

Choosing a configuration

Points to Note for Industrial Use

Storage (microSD card)

microSD cards have limited write endurance, and frequent database writes shorten their life. Use a PCIe M.2 SSD on Pi 5 or a USB SSD on Pi 4, or choose a Compute Module with eMMC for peace of mind. Making the OS read-only (overlay file system) is also effective.

Power supply

Sudden power loss can corrupt the file system. Power it from a HAT with UPS functionality or from the control panel's UPS so it can shut down safely during outages. A 5V/5A power supply is recommended for Pi 5.

Installation environment

The operating temperature of the consumer Raspberry Pi (Pi 5) is 0 to 50°C. When installing in a control panel, manage the temperature with a heat-dissipating case or fan and place it away from noise sources. In harsh environments, consider industrial controller products using a Compute Module (with environmental resistance and DIN rail mounting).

Network and security

• Separate the control and information networks as much as possible, and make access from the Raspberry Pi to the PLC "read-only"
• Do not leave the default user or password; use key authentication for SSH
• Update the OS and libraries regularly
• On the PLC side too, use settings that prohibit external writes if available

Wireless (Giteki certification in Japan)

When using Wi-Fi or Bluetooth in Japan, check that the model and lot have technical standards conformity certification (Giteki). Products bought from authorized domestic retailers are normally fine. In other countries, follow your local radio regulations.

Do not use it for control

The basic rule is to leave emergency stops, safety-related control and high-speed I/O control to the PLC and keep the Raspberry Pi on the information processing side. It is important to configure things so the equipment keeps running as before even if the Raspberry Pi stops.

Summary

The Raspberry Pi was born as a $35 educational computer and has grown into a reliable platform that is even embedded in industrial equipment.

On the factory floor, by leaving PLC control untouched and letting the Raspberry Pi collect, show and connect data, you can start visualizing equipment with a small investment.

Single-board: for data collection servers, gateways and web display. Start with a Pi 4/Pi 5.
Compute Module: for embedding in mass-produced products or control panels. eMMC makes it strong for long-term operation.
Pico: for sensor reading that needs real-time performance and for small, low-power terminals.

We recommend trying configuration 1 on one machine first, then expanding to configurations 2 to 4 once the effect is clear.

Related pages

OMRON FINS Communication

FINS communication with OMRON products from Python

KEYENCE Host Link communication

Host Link communication with KEYENCE PLCs from Python

MITSUBISHI MC protocol communication

MC protocol communication with MITSUBISHI PLCs from Python

What Is a PLC?

Explains the role and features of the PLC, and how it relates to what is often called a "sequencer" in Japan.

PLC: Beyond

Thoughts on the future evolution of PLCs

Board setup

Raspberry Pi setup

Recording PLC data in SQLite

A sample that reads PLC data every second and records it in SQLite

Sources

• Raspberry Pi official website, products page
• Raspberry Pi News: A new 3GB Raspberry Pi 4 for $83.75, and more memory-driven price increases (April 2026)
• OMG! Ubuntu: price revision of the 2GB models (October 2026)
• CircuitDigest: AMA on the Raspberry Pi 6 timeline and industrial use (May 2026)
• Raspberry Pi Product Information Portal (product specifications for each model)

Prices and availability change. Check the official website and authorized retailers for the latest information.

Image credits

Model images are from Wikimedia Commons and are used in accordance with their respective licenses.

Raspberry Pi is a trademark of Raspberry Pi Ltd.

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