DIY Workshop Remote Dust Collection
MobileDemand xTablet Hacking

As I’m deploying more LoRa nodes I find myself needing a more capable debugging system. While at home
I simply use an SDR connected to my desktop to ensure devices are transmitting as expected. In the field
that is a loftier goal. I’ve tried using an SDR connected to an Android phone with limited success, this
seems to just kill the battery more than anything.
Cacoffiny Bare PCBs for sale
Going to have a small batch of unpopulated PCBs available in the new OiT Electronics shop.
Selling these will help with a final revision of this PCB that will correct some of the mistakes that made manufacturing and bring-up too difficult to make continuing worth while.

What’s That UART?
The groundwork for getting started on this project was laid out in this 2018 EEVBlog forum post. In it, Luiz Renault suggests the data rate is 512kbit/s based on the smallest pulse width. My results before vary slightly but should be in the same range.
The minimal bit length looks to be ~1.740us, not far off Luiz’s 1.960us that can be seen in the scope shot in the second post. So 512kbit/s seems like a reasonable rounding point. Luiz also indicated they were able to decode the data, but not what the content looked like. There was also no indication of byte size, start/stop bits. So more digging….
ESP32 startup times
I found myself in a conversation about ESP32 boot times. Specifically the time it takes from boot until user code can do something useful with an IO.
As this was something relevant to Richmote but I didn’t have any actual data I decided to
do a simple setup to measure the results. My test setup consisted of two probes one connected
to the RST line and the other to a random GPIO. The firmware would immediately setup the
GPIO as an output and pull it HIGH. Nothing else.