[Settings] ──> [System Update] ──> [Check for Updates] ──> [Download & Install] Step-by-Step OTA Process

What "UPD" typically means here

Scroll down to find "System Update" or "Software Update."

If an update is available, the screen will display the new version details and a changelog. Tap .

: If a firmware update is not resolving performance issues, a hard reset (Volume Down + Power) can be performed to clear deep-seated system errors.

🚧 : The following methods are not recommended for general users. They can void warranties and, if done incorrectly, permanently damage your device. The safest way to update is always through official channels.

Remember: an outdated POS terminal is a security risk to your customers and a liability to your business. Set a calendar reminder to check for updates every 90 days. And when in doubt, always reach out to your authorized Sunmi distributor before flashing any file.

If an update is available, a changelog will appear. Tap .

Do not interrupt.

Sunmi typically does not provide public "direct download" links for firmware files (.zip or .img) to end-users to prevent accidental damage. To get the correct firmware for your specific region and hardware revision:

Sunmi provides free OS upgrades and firmware fixes for its standard products as part of its support policy. They also offer extensive developer and technical documentation on their official site, which can be a valuable resource for deeper technical issues [11†L32-L33].

Method 1: The Official & Safest Way (Over-The-Air OTA Update)

Sunmi V2 Pro checks for official signatures. If you flashed a custom ROM, reflash the official UPD from the Partner Portal.