Patent ID: 8259791

Claim:
A digital signal processing device comprising: an input terminal that includes: a TMDS signal input section having at least one pin configured to receive a TMDS signal via a digital signal cable; a hot-plug signal input section having at least one pin configured to receive a hot-plug signal via the digital signal cable; a TMDS signal determination section configured to determine whether the TMDS signal has been received; a hot-plug signal determination section configured to determine, in response to the determination that the TMDS signal has not been received, whether the hot-plug signal has been received every t seconds; and a digital signal determination section configured to determine that a digital signal is present if the TMDS signal is received, and configured to determine that the digital signal is absent if (a) the hot-plug signal has not been received n times (n being an integer equal to or greater than one), or (b) the hot-plug signal has been received m times (m being an integer equal to or greater than two and m being greater than n), wherein the TMDS signal determination section, the hot-plug signal determination section, and the digital signal determination section are each tangibly embodied as computer instructions stored on at least one non-transitory storage medium and executable by at least one processor.