Bluetooth HC-05 stuck in AT Mode


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.



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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Yes it still locks up :frowning:

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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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