RF UART, help selecting which one
evanh
Posts: 17,265
I'm about to try building my own hot water solar diverter. I've got a dead unit sitting beside me right now that cooked itself after about 10 years of operation. I've already tried repairing it but it died again after a few days of partial operation. It was fancy in that it did full smoothed modulation. Has quite a number of large inductors in it. I'm not going to attempt to replicate that. Instead I'll start with just using the existing current transformer that's still attached to the main cable from the power meter outside the house. I have it shorted. I just want to automatically control when the water heat is turned on and off. Rough plan is when export power reaches 1.8 kW turn it on, and when import power reaches 1 kW turn it off. It's a 2kW heater element.
I figure it's best to not run a data cable around the house and especially into the water heater wiring. With that in mind it seems a good idea to use a RF link of some sort. I want to be able to have rapid debugging feedback with it in circuit so I can quickly experiment with software changes. The Propellers are at home with UART serial port so I figure it's easiest to stick to that. The distance is only down the hallway, so a couple of rooms away tops.
As a first guess I'm thinking Bluetooth is the obvious choice. Or is there other more suitable options?
Looking up general info on Bluetooth I'm immediately swamped with versions and then BLE seems to be a whole new thing. My best guess is I can probably choose an old simpler, say v4, Bluetooth module for the remote device (Solar Diverter) and still be able to buy the latest USB BLE adaptor for the development computer and have them talk ... right?
Comments
That is asking for problems: https://superuser.com/questions/1510761/are-all-bt-4-5-dongles-compatible-ble
why not use an ESP C6/C5 they are not that much more expensive then pure BT adapters and allows you to choose WIFI or BT or ...
A friend of mine has a bunch of land in Pennsylvania and loves the ESP variants. In his case, though -- and he did recommend it -- was the ESPNOW protocol. I made an ESP-01 adapter that I can use on my P2 and P1 Eval boards (latter is my simple design), and I'm able to talk to the ESP-01. The next step is to make it a bridge.
If you're going to go Bluetooth I would suggest NOT using BLE. The simple modules are really easy to use as pass-through modems. If you're an Android user, you can connect with them. Several years ago I used a P1 with an HC-05 to spell out names in Christmas lights ala Stranger Things. I sent the names from a simple terminal program on an Android phone.
Yes, I want it only as a pass-through comport/modem, as if it were a Prop-plug. No programmability. So then the terminal/downloader software just thinks it's another comport. Okay, so avoid BLE.
What about for the development computer side? It's just my main desktop computer with 43" 4k monitor attached. An Android phone will be sporting the latest BLE support so I reason that buying any modern generic USB to BLE adaptor for my computer should do the job of connecting to non-BLE devices too.
That dude is asking the reverse question. He's asking if an old non-BLE adaptor will talk to BLE devices.
With the HC-05, Bob's your uncle.
I might like the HC-05's form factor too. If I use the existing wall mounts and case from the dead diverter there is a large opening at the front where the display and buttons were. That would be a great place for the antenna to poke out to get reception.
I've now gone and purchased a nice cheap USB Ugreen 5.3 BLE adaptor. Plugged it into the computer and immediately up popped the Bluetooth icon on KDE's task bar. So it looks like my install of Linux has the needed driver built in. All good there.
And thanks for the help.