Unable to read ble data on Mit app

MIT App Inventor Help
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1

I am unable to unable to read ble data on Mit app. while i have tired the third party app and receiving data.

Sketch1
Sketch11140×1773 188 KB

I am attaching a screen shot from the nRF Connect app showing what it sees. It reads the numeric attributes, but not the string attributes, from each characteristic. In other words, I see 45.46 for the humidity but not the string "Humidity," itself. Instead, I read the UUID number the string is associated with.
ble.aia (198.3 KB)
Psychrometer1.1.ino (2.3 KB)

2

blocks
blocks1090×308 35.6 KB

The If test on this event is not right.
Did you want to test If permissionName = 'BLUETOOTH_CONNECT'?

Also, using a color literal as a test is tricky.
I have been burnt by this before.
Since color values are 32 bit integers, they have to match exactly, and your eyes may have fooled you into thinking two close but different colors are the same.

blocks (1)
blocks (1)1436×568 79.8 KB

I suggest using the Text in a Label for a test value.
(Ignore this part if you actually did connect.)

1 Like
3

nrfConnect would not see that string because you did not send it, just the humidity value, which did arrive.

Your sketch looks like it is now sending correct strings to BLE.

I would concentrate on the AI2 app, to see why it is not receiving the strings now.

You might add a Label or two to the app to display unfiltered strings, to factor out any surprises in the UUIDs.

4

I have changed the app it is still not connecting to ble and not showing any data.
Paludarium_App.aia (920.3 KB)

5

I see you use both BLE and the BlueTooth Client.

I see you have

blocks
blocks1024×232 30 KB

but no After Selected event for ListView1.

I imagine that would leave your ListView1.SelectionIndex at 0?

Try a Do It on that block after selecting from ListView1 and tell us if I guessed right.

blocks (1)
blocks (1)789×6203 696 KB

6

I have updated the app and made some changes, Now it is connecting to the app but not receiving data. It is showing this error the " opertion register for strings can not accept arguments [19B10000-E8F2-537E-4F6C-D104768A1214] ["nothing"], [false] "

I am attaching updated app and code.
pakis1 (2).aia (916.2 KB)
Great_Psychrometer.txt (2.4 KB)

7

image
image786×393 26 KB

See that different color on the HUMIDITYUUID?

You disabled it, so it's missing in action when you try to register for strings using it.

Right click on it and activate it.

8

I have made the changes still the app is connecting and then crushing, unable to receive any data

9

Also, I am trying to receive values in float form, the app is connecting to device but showing nothing?

float_ble.ino (2.4 KB)
Float.aia (916.5 KB)

10

You might try bypassing those if/then checks in the FloatsReceived event, and posting those three incoming values to Labels for debugging.

Also review the difference between a device and a service at