As I long time OpenSprinker 1.4s user, I have decided it was time to upgrade to the OpenSprinkler Bee and the OpenSprinkler3.0. I use the ESP8266 in a lots of my IoT devices and so far love the nice OpenSprinkler3.0 web interface!
My question is regarding the CH340G USB chip. Should the crystal be mounted like in the photo, or is this a pick and place issue?
Also I notice my OpenSprinkler3.0 has no crystal soldered down for the CH340C, however Windows does detect the USB device and loads the driver correctly. Is this because the “C” version does not need a crystal? It’s very hard to find a datasheet on the CH340C.
The crystal was mounted that way because we ran out of the 3-SMD type crystal and had to use the 3225 type. The 3225 type (which is what you see in the picture) has 4 pins on the corner, and the crystal is across the diagonal direction (the other two pins are unconnected). In order to use it to replace the 3-pin crystal, it has to be amounted at that angle so that the diagonal pins are soldered onto the two outer pins on the 3-pin footprint. Sorry that it must have caused confusion to you.
CH340C does not need external crystal — it’s a newer version of CH340 that has built-in oscillator (and barely more expensive than Ch340G), so it’s a no-brainer replacement of Ch340G.