hello all,now I am building a bluetooth control car using arduino uno, motor shield and bluetooth module(HC-06).I want to know how I can connect rx and tx for both motor shield and bluetooth module when I am using power from arduino to motor shield.can rx and tx pins use for two devices.please help me.if you have any codes for this project please let me learn.thanks..
Most motor shields don't use RX and TX. What motor shield do you have?
On the Arduino UNO there is only one hardware serial port (Serial) and it is connected to the USB connector so you can send debug messages to a PC. You can use SoftwareSerial to talk to your bluetooth module using any two spare pins you have. SoftwareSerial causes jitter in servo outputs so if you are using the Servo library you might want a different choice. You can use Serial (Pins 0 and 1) for your bluetooth module but you will lose the ability to send debug messages to your PC.
If you use an Arduino Leonardo or Micro it has separate USB (Serial) and hardware serial (Serial1) so you can still use USB for debugging and use Serial1 (Pins 0 and 1) for bluetooth.
thank johnwasser for your reply.I used arduino uno , L293D dc motor shield and HC-06 bluetooth module.I does not clear how I can combile these three modules to control dc motors via bluetooth.I tested to control dc motors without motor shield and it is ok.(I used blue term androide app to commend from mobile). but when I use motor shield I don't know how to continue.If you have any design and code for this project please let me know.Or please let me know where I can study details for this project.This is my first project with arduino and I want to success.Thanks..