Patent ID: 8157180

Claim:
An integrated circuit device having an International Standard Organization (ISO) communication mode and a non-ISO communication mode, the integrated circuit device comprising: a CPU coupled to a bus for controlling an operation of the integrated circuit device; a serial I/O line communicatively connected to the bus to input data into the device or output data from the device based on a control of the CPU in the ISO communication mode; a plurality of data lines, separate from the serial I/O line, comprising a first data line and a second data line; a transceiver circuit coupled to the plurality of data lines to input or output data to and from the device in the non-ISO communication mode through the plurality of data lines; and a detector circuit coupled to at least one of the plurality of data lines and configured to determine whether the integrated circuit device is electrically connected to an external device, wherein the detector circuit is configured to select the ISO communication mode in response to a first state of an internally supplied signal to the at least one data line at a power up state, and is configured to select the non-ISO communication mode in response to a second state of the internally supplied signal to the at least one data line at the power up state; wherein the internally supplied signal is derived from a power supply internal to the integrated circuit device, and wherein the integrated circuit device is set to the communication mode selected by the detector circuit within a predetermined time period.