Bluetooth HC-05 stuck in AT Mode

Support
1

Hi,

I’m having a problem where my HC05 module starts up in AT mode (LED blinking every 2 seconds) and I am unable to exit out of it (by removing power) or send AT commands. Any suggestions to fix this? I have the RX/TX pins connected via a logic level converter to the TX/RX pins of an Arduino. Pin34 is not connected to anything.

Thanks,
Matthew

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2

Matthew, out of interest, if you remove the connection to the llc and power up the module, does it still lock into AT mode?

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3

Yes it still locks up :frowning:

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4

Did you boot the module into AT mode by pushing pin34 high? What happens if you pull it to ground and try again?

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