DAVEGA hardware v1.2
The current v1.1 hardware design is going to be retired in about two weeks and will be replaced by the new v1.2 design.
What’s new?
From the user perspective, the changes are very small.
- 3.3V input replaced by 5V input
- USB port replaced by USB-UART headers
The new design is more robust and should be less prone to power-loss/restart that’s sometimes experienced with the current design.
Also, it will no longer be possible to damage the units by accidentally connecting 5V where 3.3V is expected. This has happened several times in the past.
Price remains the same (for now).
Why the change?
Getting rid of the dependency on the ESP32 development boards
Depending on these boards has been a real pain. I have had several bad batches that I wasn’t able to use at all. The “good” batches still typically contained 10-20% of bad pieces. While I believe I have done a good job in quality checking and it was extremely rare that a bad piece made it all the way to the customer, this still was a major source of frustration. Sometimes I only discovered a glitch after having the whole PCB soldered up, at which point I just tossed everything into my “DAVEGA graveyard” box since trying to fix it doesn’t make sense economically.
Also, soldering the development board to the DAVEGA PCB is rather tedious since it’s necessary to do it such that the two PCBs touch in order to keep the profile thin.
Minimizing dependency on ICs
With the current global IC shortage, a minimalistic design makes a lot of sense. The v1.2 only requires the ESP32-WROOM and a voltage regulator. So far there hasn’t be a shortage of either. I’m still going to pile them up, just in case. 
What about the missing USB?
First thing to note is that it should be very rare that anyone will need to use the USB. These are the situations where people needed the USB in the past:
- I’m on v3.x, my DAVEGA froze and I need to do a clean FW installation.
- This hasn’t been reported a single time since v4.x, so I believe it’s no longer an issue.
- I need to migrate from v3.x to v4.x or from v4.x to v5.x.
- All new units will ship with v5.x. I don’t foresee a need to migrate to v6.x in the future. If there’s ever v6.x it will most likely require a completely new hardware.
- My DAVEGA got damaged and I need to transfer my data to another unit.
- This will be possible to do completely over WiFi in a near future.
Yeah, that’s all very nice but what if I still need the USB for some other reason that you didn’t think about?
The v1.2 still has UART headers where you will be able to connect an external USB-UART adapter.
I already have the adapter designed and PCBs should arrive this week. Here’s a render:
It will feature a USB-C connector and pogo pins. To connect it, you will simply press the pogo pins against the headers and hold it in place.
One nice thing about this solution is that it won’t require taking the DAVEGA out of the housing.
The adapters will be available in the DAVEGA e-shop for 10-15 EUR.