HC-05 Bluetooth module help, can not recieive data

1.1k Views Asked by At

I am writing some code for my arduino nano and I am using an HC-05 module for wireless transfer of data. I am sending my data as such. This is from the serial monitor, using a usb and regular print statements. I want to be able to recieve this data, and the store it in a csv (I know how to store incoming data). I need help recieveing my data.

22:17:46.765 -> =============================================================
22:17:47.770 -> Sleep timer:242
22:17:47.770 -> Light Sleep: 0  Deep Sleep: 0
22:17:47.805 -> Total Light Sleep: 0    Total Deep Sleep: 0
22:17:47.838 -> Total Sleep: 0
22:17:47.871 -> =============================================================

For some reason, when I connect my HC-05 to my windows desktop via bluetooth, and open a serial monitor in com ports 3 or 4, I get no read out. My ports I have it set up as so. My wireless intialization

Then, I use

MySerial.print()

, to send data, yet I get no output, same thing occurs if I use

Serial.print()

.

I tried getting a new HC-05 module, Switched out all the hardware, tried different prints including Serial and MySerial. I though i could get an output. Python code I tried to use python to extract the data, yet I get no output. I am not sure what to do here.

1

There are 1 best solutions below

0
Roman On

Not enough information, but I'll answer biased on the experience I've had with these modules. Here are instructions for changing or verifying the baud rate on the module:

https://www.instructables.com/Change-the-Baud-Rate-of-HC-05-Bluetooth-Module-Usi/

For my module, I could just send AT commands by default without putting it into AT mode. Send 'AT' to the module and it should respond with "OK".

It helps a ton if you have an ftdi cable for troubleshooting. Connect the ftdi to the HC-05, verify the baud rate and that the HC-05 is responding, open a serial monitor for the bluetooth on the pc and one for the ftdi cable. Try sending data back and forth. Also, be 100% sure you're using the correct com port for your bluetooth by unpairing and repairing and see which com port shows up.

It actually is possible to use the HC-05 for programming the Arduino as well if you set the baud rate to 115200 and figure out a way to hit reset on the Arduino as soon as the bluetooth connects(status/state goes solid). I used an ATTiny for that, but you could just use a pin on the nano connected to reset and another pin to monitor the "state" pin which is connected to the led on the HC-05. That way you can have wireless data and wireless programming if you wanted that.