1

Topic: Can't connect Bluetooth module

Hello,
I am using a DSD TECH Bluetooth Module HM10 (CC2541 Chip from TI) and the App on IOS can't connect to it.
An error message: "Device not reply".   (This module works well with DSD app.)

This is the link to DSTECH:
http://www.dsdtech-global.com/2017/08/hm-10.html

Thank you for your help.

Regards
Phil

2

Re: Can't connect Bluetooth module

Message "Device not reply" means that Bluetooth connection is established but controller do not reply. Check the HM 10 connection, baud rate, sketch code.

3

Re: Can't connect Bluetooth module

Yes, the Bluetooth connection is established (the led on HM10 stops blinking) but the message "Device not reply" appears because the registration step failed.

4

Re: Can't connect Bluetooth module

Check yourself with "If there is no connection..." in the tutorial by link https://remotexy.com/en/help/start/arduino-hc05/

5 (edited by profre 2020-03-10 20:40:17)

Re: Can't connect Bluetooth module

I am a new user and it was working fine, but only several hours. Then I could suddenly no longer connect to my Arduino Uno with DSD HC08 module.
When I click on my project name in the iPhone App the ble module starts blinking faster for a few seconds, then I see the timeout message in the app.
Update:
If I reverse the rx rx pins then I see „Registrating“ and the ble module led is no longer blinking and shows constant red light for some seconds. But then the app is saying device is not replying

6

Re: Can't connect Bluetooth module

Have you added any code to your project? Can try whit clean code from site, without additional code.
Right connection is  RX to TX and TX to RX. Check baud rate.

7

Re: Can't connect Bluetooth module

remotexy wrote:

Have you added any code to your project? Can try whit clean code from site, without additional code.
Right connection is  RX to TX and TX to RX. Check baud rate.

Yes, have added code to control servos and therefore I have used hard serial connection which was working fine for a while.

Without my code it is working, but not useful.
With soft serial it is working, but the servos are not behaving correctly which is normal according your comment in the servo example.
Any idea how to make it working ?

8

Re: Can't connect Bluetooth module

Maybe you are using the “delay” function.
Share your code for more.