High-definition multimedia interface HDMI unit and multimedia terminal

A multimedia terminal comprising at least one high-definition multimedia interface (HDMI) unit, wherein the HDMI unit is configured to connect to an HDMI interface of an external device of a source device type, and wherein the HDMI unit comprises:

• a switching circuit;
• an interface circuit configured to connect to an HDMI interface of an external device;
• and
• a processor coupled to the switching circuit and and the interface circuit and configured to:
• identify a device type of the external device connected to the interface circuit;
• and
• control the switching circuit according to the identified device type,
• wherein the switching circuit is configured to establish a connection between the HDMI interface of the external device connected to the interface circuit and a source interface circuit under control of the processor when the external device is a source device type,
• wherein the source interface circuit enables the HDMI unit to communicate with a source device type,
• wherein the interface circuit comprises a power supply configured to connect to a power port on the HDMI interface of the external device, wherein the power supply is configured to provide a constant voltage for the HDMI interface of the external device, wherein the interface circuit is further configured to:
• separately connect to a hot plug detection (HPD) pin on the HDMI interface of the external device and the processor;
• and
• output a level signal from the HPD pin of the external device to the processor, and
• wherein the processor is further configured to:
• acquire the level signal from the HPD pin;
• identify the external device as being of the source device type when a level of the level signal is less than or equal to a first preset threshold;
• and
• identify the external device as being of the sink device type when a level of the level signal is greater than or equal to a second preset threshold.

A multimedia terminal, comprising a high-definition multimedia interface (HDMI) unit configured to connect to an HDMI interface of an external device of a sink device type, wherein the HDMI unit comprises:

• a switching circuit;
• an interface circuit configured to connect to an HDMI interface of an external device;
• and
• a processor coupled to the switching circuit and the interface circuit and configured to:
• identify a device type of the external device connected to the interface circuit;
• and
• control the switching circuit according to the identified device type,
• wherein the switching circuit is configured to establish a connection between the HDMI interface of the external device connected to the interface circuit and a sink interface circuit under control of the processor when the external device is a sink device type,
• wherein the sink interface circuit enables the HDMI unit to communicate with a sink device type,
• wherein the interface circuit comprises a power supply configured to connect to a power port on the HDMI interface of the external device, wherein the power supply is configured to provide a constant voltage for the HDMI interface of the external device, wherein the interface circuit is further configured to:
• separately connect to a hot plug detection (HPD) pin on the HDMI interface of the external device and the processor;
• and
• output a level signal from the HPD pin of the external device to the processor, and
• wherein the processor is further configured to:
• acquire the level signal from the HPD pin;
• identify the external device as being of the source device type when a level of the level signal is less than or equal to a first preset threshold;
• and
• identify the external device as being of the sink device type when a level of the level signal is greater than or equal to a second preset threshold.