Use Arduino uno, arduino motor shield and HC-05 bluetooth

Can I use Arduino uno rev 3, Arduino motor shield and bluetooth module HC-05?
Is there an Arduino device to use instead of HC-05?

Most likely yes.

According to what I find, the only pins that are not used by the motor shield are the analog input pins (A0 -A5 AKA pins 14 -19). The HC05 could use software serial on any of the analog pins (the analog pins are actually digital pins with analog input as a special function).

I suggest using a software serial library with the HC05 in order to save the hardware serial (USB) for program upload, program output monitoring and debugging.

So I do not see any reason that you cannot use the motor shield and the HC05 together.


If I use SoftwareSerial BTSerial(14, 15); HC-05 do not work (it is connected but do not revice)
If I use SoftwareSerial BTSerial(6, 7); HC-05 work.

Where is tre problem?

There should be no difference. On an Uno 14, and 15 (A0 and A1) should work just fine as digital pins and they are pin change interrupt capable.

Edit: A0 and A1 are used by the motor shield. I found out just after @cattledog.

From the documentation on the Arduino Motor Shield

Input and Output
This shield has two separate channels, called A and B, that each use 4 of the Arduino pins to drive or sense the motor. In total there are 8 pins in use on this shield. You can use each channel separately to drive two DC motors or combine them to drive one bipolar stepper motor. The shield's pins, divided by channel are shown in the table below:

Function pins per Ch. A pins per Ch. B
Direction D12 D13
PWM D3 D11
Brake D9 D8
Current Sensing A0 A1
If you don't need the Brake and the Current Sensing and you also need more pins for your application you can disable this features by cutting the respective jumpers on the back side of the shield.

The Pins 14 and 15 you are using are A0 and A1 and they are used by the shield for motor functions.

Thank you.
I use A2 and A3 and everything works. My project integrates Arduino Uno, LC-05, Motor shield, Grove - OLED Display. I had read in the documentation that A0 and A1 are used but I continued to use them. Thank you for your support.

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