Abstract: A system and method for coupling a peripheral to a device such as a smart phone. In a most general embodiment, the invention includes a first circuit for converting data signals output by the peripheral to analog signals; a connector for coupling the circuit to an input port of the device; and a second circuit disposed within the device for converting analog signals to data signals. In the illustrative embodiment, the first circuit is a frequency shift key generator and the second circuit is a frequency shift key detector. A host controller is coupled to the peripheral and a microcontroller coupled to the host controller. A serial port is coupled between the microcontroller and the host controller. A communication controller is coupled between the serial port and the frequency shift key generator.

Abstract: A system and method for coupling a peripheral to a device such as a smart phone. In a most general embodiment, the invention includes a first circuit for converting data signals output by the peripheral to analog signals; a connector for coupling the circuit to an input port of the device; and a second circuit disposed within the device for converting analog signals to data signals. In the illustrative embodiment, the first circuit is a frequency shift key generator and the second circuit is a frequency shift key detector. A host controller is coupled to the peripheral and a microcontroller coupled to the host controller. A serial port is coupled between the microcontroller and the host controller. A communication controller is coupled between the serial port and the frequency shift key generator.

Abstract: A system and method for coupling a peripheral to a device such as a smart phone. In a most general embodiment, the invention includes a first circuit for converting data signals output by the peripheral to analog signals; a connector for coupling the circuit to an input port of the device; and a second circuit disposed within the device for converting analog signals to data signals. In the illustrative embodiment, the first circuit is a frequency shift key generator and the second circuit is a frequency shift key detector. A host controller is coupled to the peripheral and a microcontroller coupled to the host controller. A serial port is coupled between the microcontroller and the host controller. A communication controller is coupled between the serial port and the frequency shift key generator.

Abstract: A system and method for coupling a peripheral to a device such as a smart phone. In a most general embodiment, the invention includes a first circuit for converting data signals output by the peripheral to analog signals; a connector for coupling the circuit to an input port of the device; and a second circuit disposed within the device for converting analog signals to data signals. In the illustrative embodiment, the first circuit is a frequency shift key generator and the second circuit is a frequency shift key detector. A host controller is coupled to the peripheral and a microcontroller coupled to the host controller. A serial port is coupled between the microcontroller and the host controller. A communication controller is coupled between the serial port and the frequency shift key generator.