OTA in simple terms
OTA stands for Over The Air. Every electronic device runs on an internal program called firmware. An OTA update replaces that program with a newer version through a network connection, such as Wi-Fi.
In short: a product you have already installed can keep improving over time, without anyone having to touch it.
Why OTA updates are useful
New features
A device can gain functions that did not exist when it was bought.
Bug fixes
A software fault is solved with an update, with no need to recall the product.
Fewer site visits
No travel or shipping, even when devices are far away or hard to reach.
Always up to date
Fixes, including security fixes, can reach every device.
How an OTA update works
The path is simple: the new firmware version is published on a server and the device downloads it over the network.
Download
The device receives the new version and saves it in a separate area of memory, while the current one stays intact.
Check
Before installing it, the device verifies that the file is complete and arrived without errors.
Restart
Only then does it restart on the new version. This normally causes just a brief interruption.
Are OTA updates safe?
Yes, if the system is well designed. A properly built update allows for what can go wrong:
- Interruptions: if power or the network fails during the download, the device keeps using the previous version
- Damaged files: every file is verified before installation
- Unauthorised access: firmware can be digitally signed, so the device accepts only genuine updates
- Data and settings: these can be kept after the update
OTA updates for your ESP32 product
At StepLab we build OTA updates into ESP32-based devices. We have already done so in real projects, such as the smart battery charger and the Solaria system, updating both the firmware and the device's web pages over the network.
- We develop firmware with updates built in from the start
- We agree with you how updates should start: automatically or after user confirmation
- We assess whether an existing product of yours can be adapted
What is needed? The device must be able to reach a network and have enough memory. OTA updates software: it cannot change or add electronic components. We will help you work out what is possible in your case. See all our services on the ESP32 programmers page.
OTA update FAQ
Do I need a technician to update the device?
No, as long as the product is set up for it: the update arrives over the network. Depending on the project, it can start on its own or after user confirmation.
What happens if the power fails during an update?
In a properly designed system, the new version is written to a separate area of memory and activated only once installation is complete. If the process is interrupted, the device restarts on the previous version.
Are the device's settings erased?
Not if the firmware keeps them in a separate area of memory: at the design stage we define which data must stay unchanged after every update.
Can OTA be added to an existing product?
Often yes, if the device has a network connection and enough memory. On products not yet set up for it, the first firmware with OTA has to be installed by cable; from then on, updates can arrive over the network.
Contact us
Want to add OTA updates to your device? Write to us or give us a call.