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How Do I Make A Connection Between Two (2) Bluetooth Devices?
To connect two Bluetooth devices one of the pair must act as the Master and the other device must act as the Slave. Typically the USB adapters are Master devices, but most can switch between Master and Slave automatically. Only a Master can initiate a device discovery; the slave device can only respond to a device discovery inquiry. SLAVE devices can never initiate the discovery process. Once the Master has discovered the Slave device then it can pair and connect. Please be aware that the respective services must match. The BT44-191S/C, BT44-147 and the BT14-111S are typically configured as SPP (Serial Port Profile) devices and thus they will emulate the functions of a UART and they are defaulted as SLAVE devices. Therefore, if the USB MASTER discovers a BT44-191x then as it progresses to the “Obtain Services” function and the “Connect” function the USB Bluetooth adapter will communicate with a PC via one of the Virtual COM. ports that the upper level stack, running on the PC, will generate. The ZBA Bluetooth USB adapter is typically used as a Master, and will generate a Virtual COM. port on your PC automatically, so the PC will be able to communicate to the modules. See questions on how to connect two modules for that specific procedure.