Control Board on Order

A project log for Sprite Wand

How small an area can I cram 6 APA102-2020s?

morganmorgan 06/07/2019 at 15:440 Comments

I've been working my way through the control board, finally happy with the design and have sent it off to @oshpark.

Not a lot has changed since the previous post on this board, I did finally decide on the LSM6D as it had several things going for it.

1) Having a 3-deg gyro will allow for more flourishes when 'casting'

2) 3 extra degree, plus temperature was only $0.40 more ($2.6>$3)

3) I have 3 or 4 of them already.

I got all the important signals broken to test points on the backside. I've been wanting to give this Open Fixture a try. Apparently it runs some scripts on board file that get plugged into an OpenSCAD script to general a test jig to be laser cut. Sounds handy and something I should learn.

I also made sure to hook up the LSM6D to the ESP32s RTC_GPIO pins. This will allow me to configure it to wake up the CPU from deep sleep. The goal was to do some light weight motion detection in the ULP but as it doesn't support interrupts that wont' happen.

The Micro-32 modules should arrive tomorrow, I expect there should be no surprises there, I got technical drawings from the seller that matched the footprint I found. But if anything does go wrong, I should have a window to cancel my order.


I've been trying to get a nice rendering going but still have some figuring out to do with FreeCAD/Pov-Ray but this should give a general idea of the proportions. The final board was a bit shorter (save a $1!) but should still fit the handle nicely, which I think will come out at about 3.5" (127mm).

Alright, that's it for now. With boards inbound next thing is to do some tests to see how small of a tube I can run my wiring through. The mock up has 3.1mm which kind of dwarfs the Sprite. Might look okay? We'll see!