Error 515: Not Connected to Bluetooth device

MIT App Inventor Help
1

515

Screenshot_2025-03-10-14-49-01-57_c9147fcb9a623d74b79b16140b437c88
Screenshot_2025-03-10-14-49-01-57_c9147fcb9a623d74b79b16140b437c881080×2340 174 KB

Connected but why Error 515

2

511

512
512522×511 33.9 KB

513

3

Hello Drake - cannot see your first image:
In the Blocks Work Area, right mouse click and select "Export Blocks as Image"

ProfessorCad: Tips & Tricks Bluetooth Failure

Now, code 515 = Not connected to a Bluetooth Device

Tell us the make, model and version (e.g. Android version, Bluetooth version), of all the devices, and upload the Sketch/Script/API that drives the Bluetooth device.

4

the reply image that's my blocks image

5

Android 11. it's already connected to HC-05. but when I clicked button 3 to send a command. Error 515

6

sir can you make a .aia can send command "a" to hc-05?

7

BLE_permissions_allAndroidVersions.aia (193.3 KB)
can you fix this thanks

8

@uskiara

9

Dear @drake_acusta,
HC05 isn't a BLE device. therefore you cannot use the blocks relevant to BLE but those related to the "classic" BT instead.
image

10

when I use bluetoothclient it can't connect to hc-05. error 507 unable to connect

11

Then, are you sure you have a true HC05 or a HC08 instead ? (the latter is BLE)
Is your Android device set to Classic BT or is it set to BLE (in system's BT settings) ?

12

HC05. when I use Bluetooth serial terminal. its connect to BLE not to classic. I must prefer using MIT to make my app with voice command.

13

Sorry but I'm stumped. AFAIK HC05 is only classic BT !
Also by doing a very quick search in the web, I can't find info about HC05 working as BLE.
Can you post the data sheet of your HC05 ? Or can you post the link where you bought it, or the link of its description ?

Probably @ChrisWard or @ABG or @TIMAI2 are deeper in the matter.

1 Like
14
  1. What microcontroller board is hosting your HC05?
  2. Upload your Sketch/Script
15

Arduino Uno R3

16

Uno Sketch?

17

HC05 only supports Bluetooth Classic. BLE has some similar functionality to Classic but the UUID data sharing system cannot be used. On a Smart Phone with BLE, Classic is there too, so there are no problems, other than getting permissions correct, on Android 11 with Classic Bluetooth.

ProfessorCad: Tips & Tricks Arduino, other Microcontrollers and Related Subjects
ProfessorCad: Tips & Tricks Arduino
ProfessorCad: Tips & Tricks Bluetooth
ProfessorCad: Tips & Tricks Bluetooth Failure

ProfessorCad: Error Codes App Inventor and other Error Codes

1 Like