arduino module hc-05

[arduvin]

good morning
I have an arduino uno with a bluetooth module set as master; at about 8 m I have another bluetooth set as a slave to which I connected a proximity sensor.
The two bluetooth are connected to each other via AT commands.
My aim is to, when the proximity sensor senses something, it sends the 3.3v to the bluetooth slave, it communicates it to the master and arduino turns on the relay.
The slave together with the proximity module, I would like to power them with a battery.
my problem is:
Is there a pin on the hc05 slave bluetooth board that, when set to 3.3v, makes me switch from 0 to 3.3v or vice versa, a pin on the master hc05 bluetooth module?
Thanks if you answer me, I made a post on the forum but nobody answers me ... thanks!

 

[KlausST]

Hi,

your wiring is not clear to me.
I recommend to spend a little effort on drawing a sketch.

Is there a pin on the hc05 slave bluetooth board

If I needed to know this, then I need to read the datasheet.

I made a post on the forum but nobody answers me

can´t find another post...

Klaus

 

[FvM]

If I understand right, you want to transmit a 1-bit digital signal instead of UART data. HC-05 is a dedicated serial interface module using BT serial port profile, not intended for other uses. Serial port profile includes control signals, which could be used for the intended purpose, by I don't see control signals exposed at HC-05.

That's a pure software thing. HC-05 and similar HC-0x modules comprises CSR BC-517 bluetooth radio and a program flash. It could be shipped with a code supporting RS-232 control signals. But I didn't yet see something like this.

--- Updated Sep 23, 2021 ---

I see, that module pin 3 and 4 (next to pin 1 TX and pin 2 RX) are declared as CTS and RTS in a general hardware description. You may try if they have an undocumented function at HC-05. Also, how a static break signal is transmitted by the module pair.

--- Updated Sep 23, 2021 ---

There are discussions about HC-05 RTC and CTS signals, not very consistent. It sounds like they are either not working or acting as handshake between modem FIFO and external device. Thus not transmitted peer-to-peer.