Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
175 words
A fault-tolerant hierarchical bus system comprising: a bus master adapted to be connected to a module-requesting device through a system bus of a digital system; a root bus branch in a first level of the hierarchical bus system, the root bus branch being coupled to the bus master; a first level transceiver connected to said root bus branch; a plurality of bus segments in a second level of the hierarchical bus system, the bus segments being arranged in a grid, wherein the bus segments are coupled to the bus master through the root bus branch and the first level transceiver; a plurality of second level transceivers and bus switches coupled to the bus segments; a plurality of local bus interconnect segments in a third level of the hierarchical bus system, the local bus interconnect segments being coupled to the bus segments; a plurality of third level transceivers, each being connected to a corresponding one of the local bus interconnect segments; and a plurality of circuit modules coupled to each of said local bus interconnect segments.
Claim 2
Dependent Claim
175 words
A fault-tolerant hierarchical bus system comprising: a bus master adapted to be connected to a module-requesting device through a system bus of a digital system; a root bus branch in a first level of the hierarchical bus system, the root bus branch being coupled to the bus master; a first level transceiver connected to said root bus branch; a plurality of bus segments in a second level of the hierarchical bus system, the bus segments being arranged in a grid, wherein the bus segments are coupled to the bus master through the root bus branch and the first level transceiver; a plurality of second level transceivers and bus switches coupled to the bus segments; a plurality of local bus interconnect segments in a third level of the hierarchical bus system, the local bus interconnect segments being coupled to the bus segments; a plurality of third level transceivers, each being connected to a corresponding one of the local bus interconnect segments; and a plurality of circuit modules coupled to each of said local bus interconnect segments.
Claim 3
Dependent Claim
20 words
A bus system as in claim 1, wherein said bus switches are programmable to isolate defective bus segments and modules.
Claim 4
Dependent Claim
18 words
A bus system as in claim 2, wherein each of said bus switches includes a plurality of anti-fuses.
Claim 5
Dependent Claim
17 words
A bus system as in claim 1, wherein said circuit modules comprise active modules and spare modules.
Claim 6
Dependent Claim
16 words
A bus system as in claim 1, wherein said grid is mapped into a tree structure.
Claim 7
Dependent Claim
17 words
A bus system as in claim 5, wherein said grid is mapped into a disjointed tree structure.
Claim 8
Dependent Claim
29 words
A bus system as in claim 1, wherein each of said bus switches comprises a cross-bar switch which is programmable to connect up to four of the bus segments.
Claim 9
Dependent Claim
59 words
A bus system as defined in claim 1, further comprising: a second bus master; a second root bus branch in the first level of the hierarchical bus system, the second root bus branch being coupled to the second bus master and to the plurality of bus segments; and a second first-level transceiver connected to the second root bus branch.
Claim 10
Dependent Claim
18 words
A bus system as in claim 1, wherein said bus switches are located at vertices of the grid.
Claim 11
Dependent Claim
33 words
A bus system as in claim 1, wherein each local bus interconnect segment is connected to a corresponding bus segment between one of said bus switches and one of said second level transceivers.
Claim 12
Dependent Claim
19 words
A bus system as in claim 1, wherein four circuit modules are coupled to each local bus interconnect segment.
Claim 13
Dependent Claim
30 words
A bus system as in claim 1, wherein said first level transceiver, said second level transceivers, and said third level transceivers each include a corresponding set of bi-directional tri-state buffers.
Claim 14
Dependent Claim
23 words
A bus system as in claim 12, wherein said bi-directional, tri-state buffers can be disabled through programmable switches in said bi-directional, tri-state buffers.
Claim 15
Dependent Claim
28 words
A bus system as in claim 12, wherein each transceiver further comprises a control unit for controlling a direction of communication through the corresponding set of tri-state buffers.
Claim 16
Dependent Claim
93 words
A bus system as in claim 14, wherein each control unit receives a first pair of input signals, a second pair of input signals, and an input select signal, the input select signal having a first state which selects the first pair of input signals for use by the control unit and a second state which selects the second pair of input signals for use by the control unit, the state of the input select signal being selected in accordance with the physical location of the corresponding transceiver relative to the bus master.
Claim 17
Dependent Claim
34 words
A bus system as in claim 15, wherein each control unit provides two output signals in response to the selected pair of input signals, the output signals controlling the corresponding set of tri-state buffers.
Claim 18
Dependent Claim
25 words
A bus system as in claim 14, wherein said control unit comprises an identification register for storing a communication address which corresponds to said transceiver.
Claim 19
Dependent Claim
66 words
A bus system as in claim 17, wherein said control unit further comprises: a control register for storing information used to configure said control unit; and a comparator which is connected to receive the communication address from the identification register and a bus address from the bus master, wherein the comparator enables the control register to be loaded when the bus address matches the communication address.
Claim 20
Dependent Claim
21 words
A bus system as in claim 17, wherein said identification register comprises a non-volatile programmable element for storing the communication address.