I am looking to buy a bluetooth master and slave modules for my arduino uno’s. My question is, how do I establish a link between the two for communication? Do they both have to be on the same serial number in order to communicate with eachother?
Both units have to be powered on, but as long as you have them set to the same baud rate they will automatically pair with each-other. Once the two are paired the master will automatically look for the MAC address of the slave, but you can reset to allow it to connect to a different one by touching the VCC to the Key pin on the back of the BT2S Master.