Great news, OpenSprinkler v2.1u semi-assembled DIY kit has now been officially released and available immediately for purchase at the Rayshobby Shop! This version marks a major upgrade from the previous DIY kit v1.42u. With ATmega644 MCU, microSD card slot, and injection-molded enclosure, it not only brings the DIY kit up to speed with the fully assembled v2.0s, but it actually strives to be a little better (hence the migration on the version number) 🙂

In particular, it adds a mini-relay for general purpose switching (similar to the one on OpenSprinkler Beagle), changed the 24VAC terminal to an orange colored one with different pin spacing, and increased MCU frequency from 8MHz to 12Mhz. It also uses a USBasp bootloader built-in on the ATmega644 MCU for firmware flashing (while all previous versions use a separate ATtiny45 chip). The USBasp bootloader significantly improves the firmware upload speed, and is therefore very helpful if you are making frequent changes to the firmware. These changes are all described in the prototype sneakpeak preview post. Finally, the MCU is pre-loaded with the latest firmware 2.0.3 with several new features compared to the previous firmwares.

Another notable change is that v2.1u is the first semi-assembled DIY kit which comes with a partially assembled circuit board with through-hole components. I’ve designed it this way to help reduce the amount of soldering you have to do, while still let you enjoy the process of building, assembling, testing, and hacking the circuit. It’s a first-time experiment, so I will keep my fingers crossed.

In any case, if you’ve been waiting for OpenSprinkler DIY kits, go grab one quickly before it’s gone; if you already own an OpenSprinkler or have heard of OpenSprinkler one way or another, I would appreciate if you can help me spread the word. Thanks!