Fifty years of embedded systems. Thirty-five years of SMX.
Micro Digital is a small, privately held company that has been building software for embedded devices since before the term “embedded systems” existed. We know what works — and what doesn’t.
Who we are
Micro Digital Inc. was founded in 1975 in California and was one of the first embedded-systems software companies in the market. For our first decade we worked as an engineering firm, designing microprocessor-based products for other companies — deep-sea hydraulic valve controls, gas flow analyzers, hand-held terminals, data communications systems. That hands-on work is where SMX came from.
We are still privately held. That means we answer to our customers, not to shareholders: when a customer has a problem, fixing it comes ahead of our own product schedule.
What we build
In 1989 we released the SMX multitasking kernel, and over the following years added the middleware — TCP/IP, USB, file systems, GUI, WiFi — that turned it into the complete SMX® RTOS. SMX has been used in hundreds of devices since, and a major overhaul beginning with v4.0 in 2010 gave it a modern API and a clean foundation for what came next.
That next step is SecureSMX®, released in 2021. It uses the memory protection unit in Arm Cortex-M microcontrollers to divide firmware into fully isolated partitions, so a breach in one part of a device cannot reach the rest. In October 2025 we made SecureSMX open source on GitHub, so any team can build with it.
Support from the people who wrote the code.
Direct engineer support
Our engineers answer your questions directly — there is no help-desk layer in between — with a 24-hour response target.
No royalties, full source
Reasonably priced products with complete source code, so you are never locked out of your own device.
Try before you buy
Free evaluations, 30-day trials, and 90 days of complimentary support to get your project moving.
Buy only what you need
SMX is modular; you license the components your product uses, which keeps cost and memory footprint down.
Ready-to-run platforms
Startup code, board support, and drivers for a wide range of processors so you can begin application work on day one.
Our mission
To deliver reasonably priced, no-royalty software to embedded-system customers so they can reach market quickly — and, with SecureSMX, stay secure for the whole of a product’s working life.
Fifty years, briefly.
Micro Digital founded as an embedded design services firm
Incorporated in California
SMX multitasking kernel released
Middleware added; SMX becomes a complete RTOS
SMX v4.0 — modern API and codebase overhaul
SecureSMX released — MPU-based partition isolation for Cortex-M
SecureSMX released as open source on GitHub