Not gonna lie; I really miss when @djsundog, @cwebber , @loke, @akkartik, @freakazoid, @patrick, @requiem, and so many others who initially welcomed me to the Fediverse would post updates on their projects. It was motivational to me. And when a project update does manage to cross my feed, it still is.

Today, however, my feed is so heavily plastered over with political or economic content (almost universally negative), that I don't even see these updates anymore, if they're even being made at all.

I came here, to the Fediverse, to escape from reality a bit. It's now quickly reached the point where I now must seek out reality to escape from world consciousness.

Under no circumstances am I blaming anyone for this state of affairs, though. The world is totally a dumpster fire right now, and all manner of people who are directly affected by it have an absolute right to vent about it. I support this.

Still, I can't help but wax nostalgic of the days when my feed were more about thing hacking and less about hacking though life for basic survival.

@vertigo I've been working on a wireless, (non-wifi) programmable thermostat for our house. The base is powered by 24v AC from the HVAC system and steps it down to 5v DC. There's an ESP32 for the brains, an NRF24L01 for comms, and some relays for the interface with the HVAC system. The remote end has another ESP32, an NRF24L01, an RTC, and a digital temp sensor, along with a Nextion HMI touchscreen for user interface.

All the code is written in MicroPython. I built as much of the display logic into the Nextion as I could, and just transfer the underlying values back and forth instead of managing the controls directly. The thermostat is capable of running in either heating or cooling, as well as a four-times/temps-a-day, 7-day program mode that can either heat or cool.

I've got the case for the base designed, and the bottom of it printed and the bits mounted in it. I still need to print the top (and decide if I'm going to tweak the design to include status LEDs).

I decided to make the remote battery operated, so now I need to work a battery, charger, and a boost regulator into the design. I have the parts, I just need to finalize some things and then I can start on designing the case.

If the power is still on tomorrow, I can try to get some pictures if you're interested.

@vertigo Testing the battery setup, with and without external power.

The large black cable is a micro-USB extension with a panel-mount on one end. It's intended to be the incoming charging/programming port of the thermostat remote, and the other end will plug into the ESP32 dev board. I cut the middle of it open and interrupted the +5v so that it passed through the charger/boost converter. The small PCB on the left is a TP4056 Lithium battery charger. It takes 5v in to charge the battery, a battery, and provides the battery voltage back out. It handles charging, as well as over-charging protection and under-voltage protection to avoid damaging the battery. The PCB in the center is a boost converter, that takes the battery voltage and steps it up to 5v (as the battery voltage will vary depending on it's charge). The battery is an 18650 that also happens to have on-board over-charge/under-voltage protection, it was sold as a remote control toy battery.

Since these photos were taken, I tweaked the boost converter to output 5.005v, as close as I could get to the desired 5v. I may nudge it higher if I have stability problems with the ESP32 that it's intended to power. I seem to recall reading some comments somewhere that this particular dev board wants just a little more. I think it might have an onboard 5v regulator, in which case it would need more than 5v in order to be able to step down to 5v.

@vertigo Test of the remote unit via battery power. Seems to be happy so far. Although for some reason it seems to think it's in contact with the base (green antenna in the top-right corner of the display), which is not powered up right now. So that's something to look into.

I still need to feed the battery voltage into an analog GPIO so I can determine the battery level. And then find a battery graphic I can use for the Nextion.

The base is smart enough, that if it hasn't had a valid packet from the remote in a specific length of time, it will shut the HVAC off. So there shouldn't be any "It's stuck!" problems if the remote loses power.

Oh, hmm, I need to enable auto backlight management on the Nextion too. It's capable of doing it, I just never got around to it.

@vertigo Hmm. Only 10 minutes of data here, and making some assumptions that really need to be verified, but I think that with zero attempts to save any power whatsoever I'm looking at anywhere from 30-60 minutes of battery life.


This thing needs some power optimizations.


@vertigo Version one just might be designed to be plugged in...

Sign in to participate in the conversation

A bunch of technomancers in the fediverse. This arcology is for all who wash up upon it's digital shore.