Firmware – the tunnel at the end of the light

I think we have reached a point where the demise of firmware is clearly visible. It’s quite a way away, but now is the time to start planning, while there is still plenty of time.

Let’s be clear. If you still dream of 64k of contiguous RAM for your (application + RTOS + stack(s) + heap), then you write firmware. If your target hardware comfortably exceeds this, you write embedded software. [I know these terms aren’t universally agreed or understood, but this is how I’m using them.]

These days, fast 32-bit micro-controllers are available cheaply; RAM is the main limitation on what we can do with them. As the amount of RAM in micro-controllers increases, it will reach a point where they can support embedded software.

Embedded software is more mainstream than firmware. Applications run under grown-up OSs like Linux or Android. And they’re coded in modern languages that firmware target platforms can’t yet support. Like much modern software, embedded software is largely independent of its target hardware. It’s a different world.

When affordable micro-controllers can support embedded software, the need for firmware will start to decrease. Eventually, firmware will become a backwater, a small one. Before this happens, we firmware designers need to have expanded our skills into embedded software.

This means that we must embrace software design to a greater extent than we have in the past. Embedded software is less tolerant of, er, laxity than our smaller and simpler firmware designs. And embedded software is where the future lies. It’s what the tunnel in the title of this post leads to.

Today, firmware is a thriving discipline, and this will continue for some time. It will take a while before on-chip micro-controller RAM reaches the threshold needed to support embedded software (256k? 1M?). But when it does, the transition will be rapid, I think. Firmware will become a maintenance occupation. In my experience, many firmware-containing products stay in the field for ten years or more, sometimes a lot more. For as long as these products are supported, there will be a need for firmware designers.

So the end of firmware is visible, on the horizon, and we have years to prepare. Any improvement we decide to make in our design skills will benefit our firmware in the short term, as well as preparing us for the future. So this post is not a woe-ridden ‘the end is nigh!‘ sort of thing. It’s more like: forewarned is forearmed.

Firmware – the tunnel at the end of the light