Simple BLE NTC temperature sensor - Page 1
Forum section: electronics / projects

author: davorin
author_rank: Unknown
timestamp: February 04, 2022, 03:07:50 pm
content: Good afternoon (o;I am totally not an BLE expert...but looking for a simple project for a temporary test setup where I need to send the temperature values from a 10K NTC which is built into a tube with 1/2" threads where water flows through...So it should send values every 5 seconds.....Best would be if those nrf52840 USB dongles could be used as they can be powered externally from 1.8V - 3.6V....Inside platformio I see some Arduino Nano 33 BLE sample project which uses the nrf52840 as well....but nothing really for low power consumption mode.I hope I can avoid the official Nordic SDK/IDE as it is a nightmare (o;thanks for any pointers (o;richard

author: poorchava
author_rank: Super Contributor
timestamp: February 04, 2022, 07:04:24 pm
content: Cypress PRoC is a nice platform for that. At one point in time it was the cheapest BT module that you could program SW for without expensive toolchains.Also very easy, I managed to get connection with a smartphone like under an hour from unpacking the devkit.

author: gamalot
author_rank: Super Contributor
timestamp: February 04, 2022, 07:20:04 pm
content: The Sensirion SHT31 Smart Gadget Development Kit can be used as a reference design, it is open source, both hardware and software.https://developer.sensirion.com/archive/platforms/sht31-smart-gadget-development-kit/

author: davorin
author_rank: Unknown
timestamp: February 04, 2022, 07:26:03 pm
content: Well the problem is that I have a piece of tube with glued in NTC I have to use...There is a product called Amphito b1 that would be perfect for my testing...originally claimed to be opensource but no sources at all..and manufacturer told me that there are no plans supporting collecting data by anything else than their app which uses payload encryption...Also looked at a temperature/flow sensor from Kinetron......but it isn't available yet and manufacturer wants to charge for software mods just to be able to receive BLE data without encryption....

author: Renate
author_rank: Super Contributor
timestamp: February 04, 2022, 11:15:06 pm
content: It's always tough picking out a platform as it's difficult to see the warts/advantages without diving in. I ended up in the Cypress PSoC4 BLE world and have made a bunch of things from the CYBLE-012011-00 module. It's about $10 a pop. I'm sure some other platform is cheaper but for my quantities it hardly makes a difference. The good thing is that it runs on 2V to 5V so a 2032 cell is just fine (if you can do without blue LEDs!)

author: daniellemill
author_rank: Newbie
timestamp: February 05, 2022, 06:27:44 am
content: This is a good platform, I myself used it for my own purposes!

author: davorin
author_rank: Unknown
timestamp: February 05, 2022, 06:36:41 am
content: Hmmm...Digikey has no stock..and Mouser complicates things with export restriction...Anyway..isn't Cypress using a Windows IDE only?Update: Ah right..PSoC creator is available for Windows 32/64 only....

author: Siwastaja
author_rank: Super Contributor
timestamp: February 05, 2022, 08:15:21 am
content: Nordic Semi hardware and low-level documentation is excellent and kept simple, so it's easy to develop bare metal applications with none of their libraries or SDKs.As soon as you try to use their examples, the horror starts. I failed to even make unmodified hello world examples work. Just too many files (about 30 .c modules?), and tens of thousands of lines of code to print Hello World. I guess if you have worked in modern information technology field for a few years and somehow survived and adapted to it, and not yet developed PTSD, somehow it might work out or even make sense!?But me, for example, I was completely unable to do anything despite wasting a week or two in their examples and "documentation". But writing custom radio code is nearly trivial given their simple-to-use hardware on the register level, so that is what I went with.I don't know about using their BLE SoftDevice. I guess if you had documentation, you could just use it without further SDK. I mean, they exactly brag about the compile and link time independence enabled by the software interrupt based API. Itshouldwork by just including .h, flashing the image at the right address. But documentation is almost nonexistent, and I just couldn't find a single example that does exactly that.Luckily I didn't need communication with existing BLE systems so went with custom radio protocol. Far easier to design it from scratch, than to make sense of their BLE examples.Oh why does a LED blinker need to have a Button And LED Service Library, which is not even part of the example, but part of the SDK libraries?

author: davorin
author_rank: Unknown
timestamp: February 05, 2022, 08:25:26 am
content: Hmm...you're right...it doesn't has to be BLE at all (o;That leads me to RIOT-OS, which I used in the past successfully with the nrf dongle and other boards....though never found an example there which wakes up every now and then and sends a small payload....

author: davorin
author_rank: Unknown
timestamp: February 05, 2022, 09:22:10 am
content: Hmm...this looks rather interesting:https://forum.riot-os.org/t/interfacing-and-sending-bme280-sensor-data-over-a-ble-with-nrf52840-dongle/3390

author: Renate
author_rank: Super Contributor
timestamp: February 05, 2022, 10:31:59 am
content: Quote from: davorin on February 05, 2022, 06:36:41 amDamn. I put in two small orders in the last year for CYBLE-012011-00. At that time they were in the top couple of BLE modules by stock with about 10,000 units.Yes, there are any number of things that I could bitch about Cypress, like the fragmentation between WICED, EZ-BLE, PSoC, PRoC, PSoC Creator, Modus Toolbox...But in the end the point is to get something working.I think sticking with BLE is a good idea. It makes things easier on the receiving end that you have something normal. You can (and should) add Battery Service to your device to keep an eye on that. Don't settle for the stupid (unstructured) serial SPP. Use a custom GATT profile for your sensor.

author: parsingtheory
author_rank: Newbie
timestamp: June 16, 2022, 06:14:27 pm
content: Bluetooth module called SimpleBLE offers you a simple, easily integratable use with or without Arduino.