I have a HC-05 connected to an arduino mega via Serial2.
And I have a MIT App Inventor app running on my android phone.
I have an issue where I can successfully send serial data from my andoid phone to the arduino mega.
But I can't receive serial data on my android phone from the arduino.
The connections between the arduino and the HC-05 are definitely correct upon checking with my multimeter.
I have a voltage divider between arduino Tx and HC-05 Rx, consisting of a 10k resistor and a 18k resistor.
But I notice that most people seem to use voltage dividers in the range 1k to 3k.
And I have noticed that the HC-05 LED does not flash when the arduino is transmitting serial data to the HC-05. I assume the LED should be flashing?
Is the voltage divider I have used likely to the cause of the failure to receive data from the arduino/HC-05?