My main problem is to reduce the power consumption of the HC-05 Bluetooth module. As it may be known, such a module consumes lower and lower energy when it is in the AT Command Mode (between 1.5 and 3 mA current). Since my project requires sending real time data that change every 15seconds, I want to keep the module in the AT command mode in the 15seconds that the HC-05 don’t receive any data. I obviously believe that this kind of idea/solution will dramatically save the energy of the module. In other words, instead of keeping the module in data mode permanently, it will be set in data mode during 15seconds, and in AT command mode during 15seconds, after that it returns to the data mode and still 15seconds etc… I want to know is there any solution for that ? For example writing a bunch of C code (since my Hc-05 is directly connected to an STM32 board) to pass for the AT commande mode every 15seconds. I’ve successfully been able to pass from the AT command mode to the data mode by putting the pin 34 LOW and send the command AT+RESET from the STM32 (which is directly connected via UART to the HC-05). Now I want to know how to come back to the AT command mode without restarting or disconnecting the power supply. Is there any help please ?
Welcome to the forums! I’m not sure I’m clear on what you’re trying to do - there’s a lot of thoughts there that seem to be mixed together and it’s a bit tricky for me to grasp. I also noticed you made another post in a different thread about this with some more information.
To get to AT Command mode you need to pull pin34 high, and to exit AT command mode you need to pull pin 34 low then send AT+RESET according to the other forum thread.
Thanks Oliver for your response.
Effectively, I am asking how to enter from the data mode to the AT command mode without restarting and disconnecting any power supply. My HC-05 has the EN (enable) pin, I connected it to an STM32 pin which I gave it HIGH (3.3V). Then I restarted the power of the HC-05 and it works fine. My question is how to enter to that mode without restarting any power supply, like exactly how to exit it
So far as I understand it, it should enter AT command mode as soon as pin34 goes high. To exit AT command mode you need to pull pin 34 low then send AT+RESET
Merged from other topic:
I am asking how to enter from the data mode to the AT command mode without restarting and disconnecting any power supply. In other words, I am trying to make a driver to handle HC-05 module and now I have to switch between DATA mode to AT mode. When I try to switch backwards, it worls ( by putting off the EN pin and then send “AT+RESET” ) but from DATA mode to AT Mode I can’t reset the module. Anyhelp please ?
It’s best to stick to a single topic - else the conversation gets scattered and its difficult for people to help you
Edit: Looks like this thread got merged by the mods.
Merged from other topic:
Hello, I have a HC-05 module, directly connected to an STM32 via UART interface and connected simultaneously to a mobile application in order to exchange
real time data. I am trying to reduce the power consumption of my HC-05 BT module. After few researches, I discovered that if I set the command AT+IPSCAN and
put the Query duration (2nd parameter) and the Call duration (4th parameter) to 1, the current dramatically decreases. Thus, the energy which the BT
module consumes decreases as well. My problem is I didn’t understand how and why it decreases ? What are exatly the parameters AT+IPSCAN and what each one
does mean ?
Thank you for providing me a detailed description of the AT+IPSCAN command as well as its parameters.
The parameter order is as follows:
(Pulled from this datasheet)
And as for what they do:
Hope this clears things up for you!
I got it. Thank you so much =)