Project Hub /Basic Analog & Power Electronics/Discrete & Component Electronics/Calculators

Intermediate

RASPBERRY PI

₹5,000 – ₹15,000

1 – 2 Days

Partial Kit

Calculators

An exploration of vintage and modern calculator designs, emulations, mechanical buttons, and custom VFD and OLED display modules.

Originally published on Hackaday.io

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

Raspberry Pi 3 - Model B+ 1.4Ghz 64-bit quad-core Processor with 1 GB Ram (Original) Rs. 5,400.00
0.96 Inch I2C/IIC 4pin OLED Display Module White Rs. 349.00
2-Slot 18650 Holder with Protective Cover and On/Off Switch – Case Rs. 109.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

We don't carry yet: LCD (generic / unspecified)
Seven Segment / Nixie / VFD
Boost Converter (Step-up)
Enclosure / Box / Case

Browse all components

How It Works

The Calculators project is an advanced HMI device built around a Raspberry Pi Pico acting as the central processing unit. The Pico executes a custom calculator emulator framework written using the Arduino-Pico core, recreating vintage computational logic and behaviors. For visual output, the system integrates a dual-display approach: a modern 2.08-inch 256x64 OLED display driven by a custom SH1122 driver, alongside a vintage VFD display module (such as the ИЛЦ2-12/8Л) managed by a dedicated PT6315 VFD driver IC. Because vacuum fluorescent displays require significantly higher DC voltages than standard low-power microcontrollers can supply, an MT3608 step-up converter is integrated into the power circuitry to boost the input voltage, generating the necessary negative rails (such as -24V) required to properly bias the VFD segments and grid. User interaction is handled via a physical interface consisting of SKRRAAE010 dome switches mounted beneath custom 3D-printed buttons designed using FreeCAD and rendered or fine-tuned via Blender. The custom enclosure and button mechanics map directly to the GPIO pins of the Raspberry Pi Pico, enabling real-time matrix scanning and input processing for the vintage calculator emulation software.

Why Build This

Bridge modern microcontrollers like the Raspberry Pi Pico with vintage vacuum fluorescent display (VFD) technology and custom driver chips.

Design and assemble a complete human-machine interface (HMI) combining custom 3D-printed mechanical button enclosures with dual display architectures.

Implement complex software emulations of legacy hardware frameworks alongside custom display drivers using the Arduino-Pico toolchain.

Real-World Application

Vintage electronics restoration, retro-computing displays, custom HMI interface design, and retro gaming handheld aesthetics.

Skills You'll Learn

Embedded software emulation

VFD driver interfacing

high-voltage power boosting

custom display driver implementation

3D mechanical enclosure design

GPIO matrix scanning

Safety Precautions

Exercise caution with high-voltage step-up converters used for VFD power supplies (e.g., -24V rails).

Technology Tags

RASPBERRY PI PICO

ARDUINO

OLED

VFD

SH1122

PT6315

3D PRINTING

FREECAD

BLENDER

RETRO COMPUTING

EMULATION

Frequently Asked Questions

Why is an MT3608 step-up converter needed in this circuit?

Vacuum fluorescent displays (VFDs) require higher operating voltages, including negative voltage rails like -24V, which the Raspberry Pi Pico cannot supply on its own.

Can I use standard tactile switches instead of the SKRRAAE010 dome switches?

The custom 3D-printed buttons and enclosure are specifically tailored to the mechanical footprint of the SKRRAAE010 dome switches, so altering them would require modifying the FreeCAD files.

What programming framework is used to write the calculator software?

The project utilizes the Arduino-Pico framework along with a custom SH1122 driver and calculator emulation code.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

PRJ-00923