OpenSprinkler › Forums › OpenSprinkler Unified Firmware › Announcing OpenSprinkler Unified Firmware 2.1.7 › Reply To: Announcing OpenSprinkler Unified Firmware 2.1.7
@skyynet, I understand it’s a pain that the OS update process still requires a USB cable. This is because the microcontroller uses a USB-serial bootloader that’s simple, open-source, and has been widely used elsewhere. The bootloader is a piece of code that allows the microcontroller to overwrite its flash memory content (hence update firmware). It sounds simple but it actually is non-trivial to write as it involves low-level assembly code. I’ve looked into Ethernet-based bootloader, which would allow updating through web connection directly without any USB connection, but none is reliable and has been tested over long time. So I do not want to take the risk of deploying it. Hope this makes sense.
One thing I should mention is that with the ESP8266 WiFi chip, a lot of these legacy limitations will be eliminated completely. For example, OpenGarage, which is built around ESP8266, allows over the air (OTA) update, because OTA update is a standard feature in the SDK.