Reading value from OWON B41T+ / Bluetooth HLE?


App connects and reads data from OWON B41T+ multimeter. But i think there is some problem
with data? Should be longer [36, 240, 4, 0, 3, 0]

Also if someone could advice how to translate readed data to "multimeter form, like 12.2V DC"

Here is app inventor view and screenshot from phone


It would definitely help if you presented in the table the value that you have on the display and next to the value that the meter sends after BT. I suspect there is more data stored in these values, not just voltage. there is for sure range, switch position and other multimeter settings.

What's wrong with the native vendor supplied app?
OWON 35 _ 41 T Digital Multimeter USER MANUAL.pdf (3.4 MB)

Hello Teemu

An interesting project. The Manufacturer's User Manual is not specific about the type of value the meter sends, but why do you register for both strings and bytes - and why UTF16 strings? It looks like you are not sharing information that would help us to help you.

Exactly. It takes a large number of different measurement samples to decode the data. Preferably also from different switch positions.

ABG: I want to record one measurement at time. Not time interval :slight_smile:

UTF16 is just trial and error method type of solving.

Ill take some measurements with adjustable power supply. For now need is just DC measurements.

I found this from Arduino data glasses project(its not B41T+)

That zero (0) in the 9th byte is probably killing string reception.
Zero is a common string terminator.

I would drop the use of string related blocks, like the register for strings block, and just rely on bytes.

Also check the Designer attributes of the BLe component for any mention of how to handle null (zero) termination, just in case.

P.S. My test project had this, which you probably DON'T want ...

@Teemu83s Cool extension. Might be useful at some point soon.

Hi Teemu

You are building an App, not an extension, right?