HDMI Receiver Hot Plug State Control for Address Mapping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In the HDMI standard, a transmitter not set to be selected by the receiver cannot obtain device information stored in the receiver's memory, preventing communication and processes like address mapping and one-touch play.
Innovation Solution
The data receiver temporarily changes its hot plug state to allow data access when the transmitter changes from a non-selection to a selection state, enabling the transmitter to read address information and perform authentication and communication even in a non-selection state, using the CEC line for control information exchange.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the receiver restricts data access in non-selection state to protect device information, then security is improved, but communication capability deteriorates
Solution Approach 1:
The receiver dynamically changes the hot plug state based on the transmitter's selection status. When the transmitter transitions from non-selection to selection state, the receiver temporarily switches the hot plug state to permitted, enabling data access for address mapping and authentication, then restores it to restricted state afterward, thus adapting security levels to operational needs
Solution Approach 2:
The receiver performs preliminary authentication and address mapping by temporarily permitting data access before full content transmission begins. This preliminary action enables the transmitter to obtain necessary device information and complete authentication procedures in advance, ensuring security is established before vulnerable operations
2Loss of information
If the receiver maintains hot plug state as restricted in non-selection state, then information security is improved, but address mapping and control communication become impossible
Solution Approach 1:
The hot plug state is dynamically adjusted from a static restricted state to a conditional state that transitions between restricted and permitted based on authentication progress and selection status, enabling address mapping when needed while maintaining security as the default condition
Solution Approach 2:
The hot plug state acts as an intermediary mechanism that mediates between security requirements and communication needs. By temporarily switching to permitted state, it allows necessary information exchange for address mapping and control communication, then returns to restricted state to maintain security
3Adaptability or versatility
If the receiver allows continuous data access to enable communication, then communication capability is improved, but security against unauthorized access deteriorates
Solution Approach 1:
The receiver implements periodic state transitions where the hot plug state is temporarily permitted only during specific communication phases (address mapping, authentication) and restricted at other times. This periodic switching ensures communication capability is provided when necessary while minimizing security exposure windows
Solution Approach 2:
Security is established through preliminary authentication and state management before data access is permitted. The receiver prepares the system by setting appropriate hot plug states in advance, ensuring that data access is only enabled after proper authentication and selection confirmation, preventing unauthorized access
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This allows the transmitter to obtain necessary information and perform address mapping and control processes, such as all-off and one-touch play, even when not initially selected, enhancing communication capabilities between HDMI devices.
Implementation Method 1
a CEC line which is a two-way communication line between the transmitter (source) and the receiver (sink)
Implementation Method 2
TMDS is a digital data transmission style which causes a pair of electric conductors, such as a twisted pair cable, to transmit the clock and NRZ (Non Return to Zero) data as differential signals. This type of transmission system has an advantage in that it is strong against variations in potential difference of a transceiver, can eliminate extraneous noises by common-mode voltage removal action, and can suppress unnecessary radiation.
Data Source
Figure 1
Figure 2A~2B
Figure 3
AI summary
A data receiver (320) receives a transmission content from a source (310); the data receiver (320) includes a memory (321) for storing device information; and a control unit (325) for changing a setup of a hot plug (324), as a process of notifying the source (310) whether the data stored in the memory (321) can be obtained or not. The control unit (325) is arranged to set the hot plug (324) state as a setup indicative of being in a state where the data stored in the memory (321) is permitted to be obtained, in a selection state where the source (310) is selected as a contents input device, and control is performed to maintain a setup showing that the hot plug (324) state is in a state where data stored in the memory (321) is permitted to be obtained, in a case where the source (310) is changed to a non-selection state from a selection state in which the source (310) is selected as the contents input device.