EP0510739A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Local communication bus system and apparatuses for use in such a system
Assignee: D2B Systems Co Ltd
•
Filing: 1992-03-18
•
Granted: —
•
Expires: 2012-03-18
Abstract
Abstract A number of domestic audio/video apparatuses (10-14) are connected to a serial control bus (D2B, 16). Each apparatus is addressable via the bus as a device and contains functional elements addressable on subdevices. One apparatus (14) includes an on-screen display subdevice (41) and a first control subdevice (24). Subdevice status messages are defined whereby a control subdevice can ask to be informed of the status of a further subdevice (e.g. 26), and in particular to be informed automatically of any change in status without the need for continuous polling of subdevices. The subdevice status messages can be used to obtain early confirmation of a signal path being established through the system.
Inventors
- 👤 Harm Jan Welmer
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 02:17
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/20; H04B1/205; H04N; H04N5/00; H04N5/44; H04N5/445
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
131 words
A local communication bus system comprising a serial control bus attached to a plurality of apparatuses addressable via the bus as devices, each device including at least one functional element addressable via the bus as a subdevice, the subdevices in the system including a control subdevice and a further subdevice, the control subdevice including means for generating a subdevice status request message addressed to the further subdevice in the system, while the further subdevice includes means responsive to the subdevice status request message for returning a subdevice status message to the control subdevice, characterised in that the further subdevice includes means responsive to a change in status within the further subdevice for returning an updated subdevice status message to the control subdevice without the need for a further subdevice status request.
Claim 2
Dependent Claim
26 words
A system as claimed in Claim 1 wherein the subdevice status request message includes a field specifying whether or not updated subdevice status messages are desired.
Claim 3
Dependent Claim
48 words
A system as claimed in Claim 1 or 2 wherein the control subdevice includes means for generating a verification request message addressed to the further subdevice, the further subdevice being responsive to the verification request message to generate a message advising whether updated subdevice status will be supplied.
Claim 4
Dependent Claim
72 words
A system as claimed in Claim 1, 2 or 3 wherein the status of the further subdevice comprises a plurality of specific status variables, the said subdevice status request message being a generic subdevice status request message, not specific to any one of the specific status variables, the updated subdevice status message being transmitted automatically in response to a change in any one of the subdevice status variables of the further subdevice.
Claim 5
Dependent Claim
68 words
A system as claimed in Claim 4 wherein the further subdevice includes means for recognising each of a plurality of specific status request messages received from the control subdevice and is responsive to each such specific status request message to return the current value of a respective one of the status variables, in a specific subdevice status message, but without the facility for updated specific subdevice status messages.
Claim 6
Dependent Claim
75 words
A system as claimed in Claim 4 or 5, wherein the further subdevice has connections for user information signals and apparatuses of the system are interconnected on a one-to-one basis for the transmission of user information signals, the status variables of the further subdevice including a variable specifying the connectivity of at least part of a user information signal path as far as it lies within the device in which the further subdevice is located.
Claim 7
Dependent Claim
93 words
A system as claimed in Claim 6, wherein the control subdevice includes: means for identifying a yet further subdevice of the system as a desired source subdevice; means for addressing to the desired source subdevice a command initiating an autonomous process for establishing a user information signal path from the yet further subdevice to the further subdevice; and means for addressing to a further subdevice a request for updated subdevice status messages so as to gain early confirmation of the establishment of the signal path by way of an updated subdevice status message.
Claim 8
Independent Claim
43 words
An apparatus for use in a system as claimed in any preceding claim, the apparatus including an interface to a serial control bus and at least one functional element addressable as and having the technical features of the further subdevice of the system.
Claim 9
Independent Claim
50 words
An apparatus for use in a system as claimed in any of Claims 1 to 7, the apparatus including an interface to a serial control bus and at least one functional element, the functional element being addressable as and having the technical features of the control subdevice of the system.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.