I am trying to make a Bluetooth controlled robot and have troubles with the Bluetooth modules. I used 3 HC-06 Bluetooth module. All of them have different problems.
- I could not find the 1st HC-06 under the list of Bluetooth devices in the settings.
- The 2nd HC-06 could be paired with the phone but I could not send the message on the Bluetooth terminal app (The error message from the app is below).
- The 3rd HC-06 could be paired and I could send a message but the message was not registered on the Arduino nor on serial monitor. On the Bluetooth terminal app, the message was received but not replied.
What could be the problem? I'm pretty sure my connections are correct as I have checked them and they used to work.
