Part of my project to write new firmware for the Aqara E1 Zigbee light switches involved implementing the Zigbee Cluster Library OTA Update function. It didn’t go particularly smoothly, with two main obstacles. Firstly:

Sanity check - Blinky For an initial sanity check, I modified the NXP SDK’s blinky example for the 4 LEDs of the Aqara QBKG41LM (DIO lines identified here) to make sure that it would accept and run new firmware.

Before progressing too far into the design/coding process, it’s useful to put down on “paper” a list of required and desired functionality, as well as a very preliminary idea of how the various pieces might be implemented.

Aqara are one of the few manufacturers producing affordable, well built, Zigbee “compatible” light switches that are both available in my part of the world, and suitable for local electrical installations. Aqara are a brand of Xiaomi-backed Lumi United Tech.

Full SWD/JTAG debugging is great wherever possible, but sometimes it’s not available, or a device is being tested in a production environment, or is perhaps in production.

Firmware design for the Bluetooth audio player project. The basic architecture uses events to trigger external interrupts. Handlers post the event details into a queue and a simple control loop polls the queue and dispatches events to various handlers.

This is part 4 of a 4-part series on building a toaster reflow oven: Oven hardware Controller hardware Manufacturing Controller software Continuing on from the prior posts on the controller hardware and manufacturing, the device needs software.

Building an automatic water manager for a vertical garden wall.