Fig. 4

Application control flow. a The main application is initialized by a daemon script—or background running process—that ensured the program was always running while the computer was on. The computer application ran multiple coroutines asynchronously to allow for nearly uninterrupted data streaming between input and output devices as well as for Bluetooth communication. b The main application process iteratively made calls to classes that manage input and output devices. These device manager classes contained public methods for obtaining device input and sending commands to output devices. These device classes communicated with their hardware counterpart over serial port communication. Importantly, an array of devices may exist for the subject to use. These could be individually selected via the App over BLE