Hexadecimal Decoder Attachment for the Modular Mechanical Binary Counter

Now with an A1 Mini compatible profile!

A fully mechanical, hexadecimal display for decoding 4-bits from the Modular Mechanical Binary Counter with a steam punk feel.

This project features a fully mechanical display that converts a 4‑bit binary (nibble) into a hexadecimal digit using a 13-dot-style hexadecimal display.
 

The Hexadecimal Decoder mounts directly to the top of the Binary Counter, reading the state of four connected Bit Modules. Each binary state is mechanically translated into a visible hexadecimal digit using a dot‑card and mask arrangement.
 

This module is designed for educational demonstration and tactile fun, showing how binary values can be represented in hexadecimal without any electronics.

What's new?

V1.1

- A1 Mini Support!

- Thickened colored marks on Decoder Card and increased bottom shell layers to reduce color bleed from back side
- Fixed left and right hex midline hex shapes on Decoder Mask
- Added alternate version of Card Mask filling all hex holes to help with contrast of marks on Decoder Mask
- Added alternate stand-off with 1mm extra separation as an option if the Decoder Card drags on the Decoder Mask

What you will need

The Hexadecimal Decoder relies on the mechanical output from the Binary Counter. So you will need a minimum of a 4-bit build of the Modular Mechanical Binary Counter System.
 

The only other required, non-printed parts are rubber bands. 

• Qty 4: 16mm rubber bands (Bambu sells them in a 100 pack - so Qty 1)
• ~ 175g of filament
• ~ 7 printing hours
• ~ 30 assembly minutes

If you bought the pack from Bambu for the Binary Counter system, you should plenty left over.

Included Profiles

• Hexadecimal Decoder v1.1: The full decoder project
• Hexadecimal Decoder v1.1 - A1 Mini: A modified version to fit the A1 Mini plate - the Main Block is split into peices that fit together

Here is the system with 8 bits (a full byte) spinning.

On the roadmap

I hope to see if I can make adjustments to the Main Block to make it A1 Mini friendly.
 

Why?

I was looking for a complex project to learn and stretch design skills. I somehow settled on the Modular Mechanical Binary Counter System.

Then, somehow, I thought it would be cool if I could decode the nibble (4 bits) into a it's hexadecimal representation. So I ended up developing both projects in tandem.

For the decoder, I had hoped to do a traditional 7 segment display. I have seen a few mechanical 7 segment displays, but it soon became clear that it would be way too complex to mechanically convert the inputs into a form that could drive a 7 segment display. There are just to many ORs and ANDs involved. So I finally settled on using a dot card behind a mask into a ‘13 dot’ display.