2 open source boards using the W65C21N

Real designs built with the W65C21N, from public GitHub projects: a quick way to see how others power, decouple and connect it. Each board comes with its KiCad files, full parts list and a render — and you can simulate its firmware on HardLabs.

The W65C21N in open source designs

The gallery holds 2 open source boards using the W65C21N from 2 GitHub repositories; a typical one measures about 262.5 × 107.9 mm and carries around 271 components.

100% are two-layer designs, the rest use four layers or more, and 100% carry an open source license.

The most starred is Econopet by DLehenbauer.

Microcontrollers on boards using the W65C21N

What boards using the W65C21N are built for

W65C21N: common questions

Where can I find a W65C21N reference design?

Each of the 2 boards on this page is a real design using the W65C21N. Open one to see how it is wired up, with the full BOM, a render of the layout and links to its KiCad files.

What parts are used alongside the W65C21N?

The 74LS145, 74LS245, AS6C1008, LM317AG-TN3-R and RP2040 appear in the most repositories here.

Which microcontrollers do boards using the W65C21N use?

Most are built on RP2040/RP2350 (2).

How big is a typical board using the W65C21N?

The median is 262.5 × 107.9 mm, and 100% are two-layer designs.

What is the most popular open source board using the W65C21N?

By GitHub stars, Econopet by DLehenbauer, with 18 stars.

Can I simulate one of these boards using the W65C21N before building it?

Yes. HardLabs turns a board's netlist and BOM into a working simulation, so you can boot and test firmware against it with no hardware on your desk.

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