Firmware

Firmware is software embedded in a hardware device to control how it operates. Unlike an operating system or an application, it is written into the device's ROM or flash memory and survives a power cycle. Routers, printers, cameras, IoT devices - nearly all electronics run on firmware.

The clearest example in QR code work is a dedicated QR code reader, or handheld scanner. Its image processing algorithms and decode engine sit in firmware, so an update can raise scan speed and add support for a new symbology. It is worth separating two different things that both get called a new QR code standard. The rectangular rMQR (ISO/IEC 23941) is a genuinely different symbol structure, so the decode engine - the firmware - has to be updated. Japan's unified local tax QR code (eL-QR), by contrast, keeps the ordinary QR symbology and only specifies the data format of the payment details carried inside it, so existing readers can already scan it; what needs updating is the application or back-office system that interprets the decoded string. GS1 Digital Link falls in the same category: it is a URI syntax standard, not a symbology. POS terminal updates for GS1 QR codes usually belong to this second group as well.

Smartphone scanning needs one more distinction. Firmware does drive the image sensor and the image signal processor, but the scanning feature itself lives in the operating system and app layer. When iOS 11 built QR code scanning into the Camera app, that was an OS feature addition, not a firmware change - and the same holds when an OS update appears to improve recognition accuracy.

On the security side, leaving a firmware vulnerability unpatched can turn the reader itself into an entry point. With a known flaw still present, an attacker may alter scanner behaviour so that a scan result is redirected to an unintended URL. Keeping firmware current matters most for networked commercial scanners.