Solution for consumer electronics control

Abstract

The preferred embodiment of the present invention presents a method and a device for a host control unit to communicate over a protocol compliant bus via the introduction of an auxiliary command control unit that handles communications to and from the protocol compliant bus. The auxiliary command control unit converts the high level commands of the host control unit to low-level protocol compliant electrical signals for transmission across the bus and further converts low-level protocol compliant electrical signals received from the bus into high level commands for use by the host processor.

1 . A consumer electronics control (CEC) protocol compliant device comprising: 
 a host control unit, the host control unit adapted to generate commands;    a first port for connection to a multi-conductor bus including a CEC line; and    a command control unit connected to the host control unit and to the CEC line and being adapted to convert the commands to CEC frames.    
   
   
       2 . The device of  claim 1  wherein the CEC frames contain bits represented by logical 0s and logical 1s, wherein the logical 0 is represented by an output voltage of between about 0V to about 600 mV lasting for 1.5 ms and an output voltage of between about 2.5V to about 3.6V lasting for 0.9 ms, and the logical 1 is represented by an output voltage of between about 0V to about 600 mV lasting for 0.6 ms and an output voltage of between about 2.5V to about 3.6V lasting for 1.8 ms.  
   
   
       3 . The device of  claim 1  wherein the command control unit is built into the host control unit and wherein the command control unit has a common processor used by the host control unit.  
   
   
       4 . The device of  claim 1  wherein the command control unit is connected to the host control unit by a bi-directional link.  
   
   
       5 . The device of  claim 1  further comprising: 
 a storage device connected to the command control unit wherein the storage device stores recognizable messages received from the host control unit;    wherein each of the recognizable messages comprises: 
 a length byte indicating the total number of bytes of the recognizable message;  
 a core command byte predefined to instruct the command control unit;  
 a header byte; and  
 a byte of checksum of the recognizable message.  
   
   
   
       6 . The device of  claim 5  wherein the recognizable messages further comprise at least one data byte.  
   
   
       7 . A consumer electronics control (CEC) protocol compliant device comprising: 
 a host control unit;    a command control unit connected to the host control unit and a CEC bus and being adapted to communicate through the CEC bus, wherein the command control unit: 
 supports a CEC protocol;  
 detects an interrupt from the CEC bus; and  
 switches the command control unit to either an initiator or a follower, wherein the initiator has the functions of: 
 receiving a first high-level command from a host control unit;  
 converting the first high-level command into a first CEC frame;  
 transmitting the first CEC frame to a remote command control unit via a CEC line;  
 
 and wherein the follower has the functions of: 
 receiving a second CEC frame from the CEC bus;  
 converting the second CEC frame into a second high-level CEC command; and  
 sending the second high-level command to the host control unit.  
 
   
   
   
       8 . The device of  claim 7  wherein the first and second high-level CEC commands and the format of the first and second CEC frames are defined by the CEC protocol.  
   
   
       9 . The device of  claim 7  wherein the command control unit is built into the host control unit and wherein the command control unit has a common processor used by the host control unit or a separate processor.  
   
   
       10 . The device of  claim 7  wherein the command control unit is separated from the host control unit and wherein the command control unit is connected to the host control unit by a bi-directional link.  
   
   
       11 . A method of handling consumer electronics control (CEC) commands, the method comprising the steps of: 
 transmitting a first CEC command originated from a host control unit to a remote command control unit, the first CEC command being transmitted by a first command control unit connected to the host control unit; and    receiving a second CEC command from a remote command control unit and sending to the host control unit, the second CEC command being received by the first command control unit;    wherein the host control unit, the first command control unit and the remote command control unit are CEC compliant; and    wherein the first and second CEC commands are defined by a CEC protocol.    
   
   
       12 . The method of  claim 11  further comprising the steps of: 
 detecting CEC line interrupts;    receiving the second CEC command if a CEC line interrupt is detected; and    transmitting the first CEC command and waiting for a signal free time if no interrupt is detected and the first CEC command is ready for transmitting.    
   
   
       13 . The method of  claim 11  wherein the step of transmitting the first CEC command to a remote command control unit comprises the steps of: 
 converting the first CEC command into a recognizable command in the host control unit;    sending the recognizable command to the first command control unit;    receiving the recognizable command into the first command control unit;    converting the recognizable command into a CEC frame consisting of a start bit and at least one block, wherein the CEC frame is CEC compliant;    transmitting the CEC frame via a CEC line; and    re-transmitting the CEC frame if no acknowledgement is received for any block of the CEC frame.    
   
   
       14 . The method of  claim 13  wherein the recognizable command comprises: 
 a length byte indicating the total number of bytes of the recognizable command;    a core command byte predefined to instruct the command control unit;    a header byte; and    a byte of checksum of the recognizable command.    
   
   
       15 . The method of  claim 14  wherein the recognizable command further comprises at least one data byte.  
   
   
       16 . The method of  claim 12  wherein the step of receiving the second CEC command is performed if an interrupt is detected from the CEC line during the step of waiting for the signal free time.  
   
   
       17 . The method of  claim 11  wherein the step of receiving the second CEC command from the remote command control unit comprises the steps of: 
 detecting CEC line interrupts;    receiving a CEC frame;    checking for error for the CEC frame; and    sending the CEC frame to the host control unit in a format recognized by the command control unit and the host control unit.    
   
   
       18 . A method of handling consumer electronics control (CEC) commands, the method comprising the steps of: 
 initializing a command control unit for establishing a communication path between a host control unit and the command control unit;    enabling the command control unit for CEC line interrupts;    sending a first CEC command from a host control unit to the command control unit;    waiting for a signal free time;    transmitting the first CEC command to a remote command control unit;    receiving a second CEC command from a remote command control unit by the first command control unit; and    sending the second CEC command to the host control unit.    
   
   
       19 . The method of  claim 18  wherein the first and second CEC commands are defined by CEC protocol.  
   
   
       20 . The method of  claim 18  wherein the step of receiving a second CEC command is performed if an interrupt is detected from the CEC line during the step of waiting for the signal free time.  
   
   
       21 . The method of  claim 18  wherein the step of transmitting the first CEC command to a remote command control unit comprises the steps of: 
 converting the first CEC command into a recognizable command in the host control unit;    sending the recognizable command to the command control unit;    receiving the recognizable command into the command control unit;    converting the recognizable command into a first CEC frame consisting of a start bit and at least one block, wherein each block of the first CEC frame consists of one byte received from the host control unit at bits  1  through  8 , an end of message bit at bit  9  and an acknowledgement bit at bit  10 ; and    transmitting the first CEC frame to the remote command control unit;    checking acknowledgement from the remote command control unit;    retransmitting the first CEC frame if receipt of any block of the first CEC frame is not acknowledged; and    continuing transmittal until all blocks of the first CEC frame are transmitted.    
   
   
       22 . The method of  claim 21  wherein the recognizable command comprises: 
 a length byte indicating the total number of bytes of the recognizable command;    a core command byte predefined to instruct the command control unit;    a header byte; and    a byte of checksum of the recognizable command.    
   
   
       23 . The method of  claim 22  wherein the recognizable command further comprises at least one data byte.  
   
   
       24 . The method of  claim 18  wherein the step of receiving the second CEC command from the remote command control unit comprises the steps of: 
 detecting CEC line interrupts;    receiving a CEC signaling and converting the CEC signaling into either start bits, logical 0s or logical 1s;    checking for error of the CEC signaling;    converting the logical 0s and the logical 1s into a bit stream;    acknowledging if the bit stream constructs a byte;    converting the byte into a message recognizable to the host control unit; and    sending the message to the host control unit.    
   
   
       25 . The method of  claim 24  further comprising the steps of: 
 receiving a logical bit, the logical bit being a logical 0 or a logical 1;    decreasing a bit counter by 1;    shifting the bit from right to left in a shift register if the bit counter is greater than 0;    after the first eight bits are received and a byte is constructed, checking whether the second CEC command is intended to be received by the command control unit or not, and dropping the byte if the command control unit is not an intended receiver;    putting the CEC byte into a storage device connected to the command control unit and sending an acknowledgement to the remote command control unit;    dropping the byte if the storage device has no space available; and    enabling the command control unit for CEC line interrupt.    
   
   
       26 . A system comprising: 
 a plurality of high-definition multimedia interface (HDMI) nodes interconnected, each including: 
 a host control unit;  
 a command control unit compliant with a CEC protocol wherein the command control unit is connected to the host control unit;  
 a bi-directional CEC link compliant with the CEC protocol and interconnecting the command control units of the HDMI nodes;  
   wherein each of the command control units is adapted to: 
 receive a first high-level command from a host control unit in a format recognizable for the host control unit and the command control unit;  
 transmit the first high-level command to a remote command control unit as a first CEC frame via the bi-directional link;  
 receive a second high-level CEC command from the bi-directional link as a second CEC frame;  
 send the second CEC frame to the host control unit in a format recognizable for the host control unit and the command control unit; and  
 convert the recognizable command into a second high-level CEC command;  
 wherein the first and second CEC frames and the first and second high-level CEC commands are CEC compliant.  
   
   
   
       27 . A CEC compliant device comprising: 
 a first port adapted for connection to an HDMI compliant bus;    a host control unit coupled to the first port;    a second port adapted for connection to a CEC compliant bus; and    a command control unit coupled to the second port and to the host control unit, the command control unit adapted to receive commands from the host control unit and to convert said commands to CEC compliant frames.    
   
   
       28 . The CEC compliant device of  claim 27  wherein the first port and the second port are combined in a single socket.  
   
   
       29 . An audio/visual entertainment system comprising: 
 a display device;    a content playback device;    a first bus interconnecting the display device and the content playback device;    a second bus interconnecting the display device and the content playback device;    the display device including a first host control unit and a first command control unit, the first command control unit being adapted to communicate a command with the first host control unit and to transmit or receive the command over the second bus in a format that conforms to a pre-defined protocol; and    the content playback device including a second host control unit and a second command control unit, the second command control unit being adapted to receive or send the command on the second bus and to communicate the command with the second host control unit.    
   
   
       30 . The audio/visual entertainment system of  claim 29  wherein said display device is selected from the group consisting essentially of a television and a speaker, and wherein the content playback device is selected from the group consisting essentially of a DVD player, a CD player and a VCR.  
   
   
       31 . The audio/visual entertainment system of  claim 29  wherein said first bus is an HDMI compliant bus and said second bus is a CEC compliant bus.  
   
   
       32 . The audio/visual entertainment system of  claim 29  wherein said first host control unit includes a first processor and said first command control unit includes a second processor.  
   
   
       33 . The audio/visual entertainment system of  claim 29  wherein said first host control unit and said first command control unit share a common processor.  
   
   
       34 . The audio/visual entertainment system of  claim 29  further comprising an audio/visual receiver connected to the television and the DVD player via the first bus and the second bus.