US5754777A
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Apparatus and method for distributed arbitration of shared resources
Assignee: Advanced Micro Devices Inc
•
Filing: 1995-05-05
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Granted: 1998-05-19
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Expires: 2015-05-05
Abstract
Abstract A novel distributed arbitration apparatus in accordance with this invention includes a plurality of electrical devices, such as Industry Standard Architecture (ISA) hub cards, that independently determine availability of a shared resource, such as a bus that interconnects the devices, by use of an arbiter. When a circuit in an electrical device needs to use the bus, the circuit drives a request signal active to an arbiter, for example, in the form of a programmable logic device, such as a Programmable Array Logic (PAL™) device included in the electrical device. The arbiter in turn transmits the request signal to all other arbiters. Therefore, each arbiter receives and monitors request signals from all circuits. If only one request signal is active at a given time, all arbiters receive the active request signal and each arbiter drives an acknowledge signal active to the respective local circuit. The circuit that requested the shared resource then uses the resource. If more than one request signal is active simultaneously, each arbiter determines the occurrence of a collision, and drives a collision signal active to the respective local circuit that then implements a backoff algorithm.
Inventors
- 👤 Sherman Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:51
CPC Classifications
G; G06; G06F; G06F13/00; G06F13/38; G06F13/40; G06F13/4063; G06F13/409; G06F12/00; G06F12/02; G06F12/06; G06F12/0646; G06F12/0669; G06F12/0676; G06F13/14; G06F13/36; G06F13/368; G06F13/376
Claims Analysis
Total Claims: 59
Claim 1
Independent Claim
233 words
A system comprising a plurality of electrical devices coupled to one another through a bus, each electrical device comprising: a circuit having a local request line and an acknowledge line; an arbiter comprising (i) a local request terminal coupled to said local request line, (ii) an acknowledge terminal coupled to said acknowledge line, (iii) a plurality of remote request terminals, each remote request terminal being coupled through said bus to a local request line of a circuit of an electrical device other than said electrical device and (iv) an identity terminal coupled to a second apparatus terminal of an identity apparatus, said second apparatus terminal being coupled inside said identity apparatus to a first apparatus terminal, such that presence of coupling between said first apparatus terminal and said second apparatus terminal indicates an identity to said arbiter when said arbiter is coupled to said identity apparatus; wherein said arbiter drives a signal active on said acknowledge terminal in response to an active signal on said local request terminal and in absence of an active signal on any of said remote request terminals; wherein said first apparatus terminal is coupled through a pull-up resistor to a voltage source in said electrical device, when said electrical device is coupled to said identity apparatus, said voltage source supplying a signal of an approximately fixed predetermined voltage level indicative of a logic state in said electrical device.
Claim 2
Independent Claim
233 words
A system comprising a plurality of electrical devices coupled to one another through a bus, each electrical device comprising: a circuit having a local request line and an acknowledge line; an arbiter comprising (i) a local request terminal coupled to said local request line, (ii) an acknowledge terminal coupled to said acknowledge line, (iii) a plurality of remote request terminals, each remote request terminal being coupled through said bus to a local request line of a circuit of an electrical device other than said electrical device and (iv) an identity terminal coupled to a second apparatus terminal of an identity apparatus, said second apparatus terminal being coupled inside said identity apparatus to a first apparatus terminal, such that presence of coupling between said first apparatus terminal and said second apparatus terminal indicates an identity to said arbiter when said arbiter is coupled to said identity apparatus; wherein said arbiter drives a signal active on said acknowledge terminal in response to an active signal on said local request terminal and in absence of an active signal on any of said remote request terminals; wherein said first apparatus terminal is coupled through a pull-up resistor to a voltage source in said electrical device, when said electrical device is coupled to said identity apparatus, said voltage source supplying a signal of an approximately fixed predetermined voltage level indicative of a logic state in said electrical device.
Claim 3
Dependent Claim
14 words
The system of claim 1 wherein said predetermined voltage level is the Vcc reference.
Claim 4
Dependent Claim
14 words
The system of claim 1 wherein said predetermined voltage level is the ground reference.
Claim 5
Dependent Claim
23 words
The system of claim 1, wherein said apparatus terminals and a plurality of terminals of said bus are included in a single connector.
Claim 6
Dependent Claim
23 words
The system of claim 4, wherein said connector is one of a plurality of connectors of a system board included in said system.
Claim 7
Dependent Claim
22 words
The system of claim 4, wherein said connector is one of a plurality of connectors of a cable included in said system.
Claim 8
Dependent Claim
60 words
The system of claim 1, wherein: said circuit includes a repeater circuit having a collision line; and said arbiter further comprises a collision terminal coupled to said collision line, and in response to said active signal on said local request terminal and an active signal on any remote request terminal said arbiter drives a signal active on said collision terminal.
Claim 9
Independent Claim
208 words
A system comprising a plurality of electrical devices coupled to one another through a bus each electrical device comprising: a first circuit having a first line and a second line; a second circuit comprising (i) a first terminal coupled to said first line, (ii) a second terminal coupled to said second line, (iii) a plurality of third terminals, each third terminal being coupled through said bus to a first line of a first circuit of an electrical device other than said electrical device, and (iv) an identity terminal coupled to a second apparatus terminal of an identity apparatus, said second apparatus terminal being coupled inside said identity apparatus to a first apparatus terminal, such that presence of coupling between said first apparatus terminal and said second apparatus terminal indicates an identity to said second circuit when said first apparatus terminal and said second apparatus; wherein: said second circuit drives a signal active on said second terminal in response to an active signal on said first terminal and in absence of an active signal on any of said third terminals; and each of said electrical devices comprises a plurality of identity terminals, each unique combination of signals on said identity terminals indicating a unique identity to an electrical device.
Claim 10
Independent Claim
208 words
A system comprising a plurality of electrical devices coupled to one another through a bus each electrical device comprising: a first circuit having a first line and a second line; a second circuit comprising (i) a first terminal coupled to said first line, (ii) a second terminal coupled to said second line, (iii) a plurality of third terminals, each third terminal being coupled through said bus to a first line of a first circuit of an electrical device other than said electrical device, and (iv) an identity terminal coupled to a second apparatus terminal of an identity apparatus, said second apparatus terminal being coupled inside said identity apparatus to a first apparatus terminal, such that presence of coupling between said first apparatus terminal and said second apparatus terminal indicates an identity to said second circuit when said first apparatus terminal and said second apparatus; wherein: said second circuit drives a signal active on said second terminal in response to an active signal on said first terminal and in absence of an active signal on any of said third terminals; and each of said electrical devices comprises a plurality of identity terminals, each unique combination of signals on said identity terminals indicating a unique identity to an electrical device.
Claim 11
Dependent Claim
23 words
The system of claim 8, wherein said apparatus terminals and a plurality of terminals of said bus are included in a single connector.
Claim 12
Dependent Claim
23 words
The system of claim 9, wherein said connector is one of a plurality of connectors of a system board included in said system.
Claim 13
Dependent Claim
22 words
The system of claim 9, wherein said connector is one of a plurality of connectors of a cable included in said system.
Claim 14
Dependent Claim
61 words
The system of claim 8, wherein said first circuit includes a repeater circuit having a third line; and said second circuit further comprises a fourth terminal coupled to said third line, and in response to said active signal on said first terminal and an active signal on any third terminal said second circuit drives a signal active on said fourth terminal.
Claim 15
Dependent Claim
15 words
The system of claim 8 wherein said first circuit is included in an integrated circuit.
Claim 16
Dependent Claim
16 words
The system of claim 8 wherein said second circuit is included in a programmable logic device.
Claim 17
Dependent Claim
21 words
The system of claim 8 wherein said first circuit and said second circuit are both included in a single integrated circuit.
Claim 18
Dependent Claim
22 words
The system of claim 8 further comprising a user configurable element, wherein said identity terminal is coupled to said user configurable element.
Claim 19
Dependent Claim
13 words
The system of claim 16 wherein said user configurable element is a jumper.
Claim 20
Dependent Claim
30 words
The system of claim 8 wherein said first apparatus terminal is coupled to a voltage source in said electrical device when said electrical device is coupled to said identity apparatus.
Claim 21
Independent Claim
313 words
A system comprising a plurality of electrical devices coupled to one another through a bus each electrical device comprising: a circuit having a local request line and an acknowledge line: and an arbiter comprising (i) a local request terminal coupled to said local request line, (ii) an acknowledge terminal coupled to said acknowledge line, and (iii) a plurality of remote request terminals, each remote request terminal being coupled through said bus to a local request line of a circuit of an electrical device other than said electrical device, wherein said arbiter drives a signal active on said acknowledge terminal in response to an active signal on said local request terminal and in absence of an active signal on any of said remote request terminals; the system further comprising: an identity apparatus comprising a housing and a connector supported by said housing, said connector comprising a plurality of apparatus terminals including said first apparatus terminal and said second apparatus terminal, wherein when an electrical device is coupled to said connector: said first apparatus terminal of said plurality of apparatus terminals is coupled to a first device terminal in said electrical device, said first apparatus terminal carrying a first signal supplied at said first device terminal, said first signal having an approximately fixed predetermined first voltage level; and said second apparatus terminal of said plurality of apparatus terminals is coupled to a second device terminal in said electrical device, said second apparatus terminal carrying a second signal supplied at said second device terminal, said second signal having a predetermined fixed second voltage level; wherein said first apparatus terminal is coupled inside said identity apparatus to said second apparatus terminal, said second signal appears on said first device terminal and thereby indicates a second identity to said electrical device different from a first identity indicated by appearance of said first signal on said first device terminal.
Claim 22
Independent Claim
313 words
A system comprising a plurality of electrical devices coupled to one another through a bus each electrical device comprising: a circuit having a local request line and an acknowledge line: and an arbiter comprising (i) a local request terminal coupled to said local request line, (ii) an acknowledge terminal coupled to said acknowledge line, and (iii) a plurality of remote request terminals, each remote request terminal being coupled through said bus to a local request line of a circuit of an electrical device other than said electrical device, wherein said arbiter drives a signal active on said acknowledge terminal in response to an active signal on said local request terminal and in absence of an active signal on any of said remote request terminals; the system further comprising: an identity apparatus comprising a housing and a connector supported by said housing, said connector comprising a plurality of apparatus terminals including said first apparatus terminal and said second apparatus terminal, wherein when an electrical device is coupled to said connector: said first apparatus terminal of said plurality of apparatus terminals is coupled to a first device terminal in said electrical device, said first apparatus terminal carrying a first signal supplied at said first device terminal, said first signal having an approximately fixed predetermined first voltage level; and said second apparatus terminal of said plurality of apparatus terminals is coupled to a second device terminal in said electrical device, said second apparatus terminal carrying a second signal supplied at said second device terminal, said second signal having a predetermined fixed second voltage level; wherein said first apparatus terminal is coupled inside said identity apparatus to said second apparatus terminal, said second signal appears on said first device terminal and thereby indicates a second identity to said electrical device different from a first identity indicated by appearance of said first signal on said first device terminal.
Claim 23
Dependent Claim
17 words
The system of claim 19 wherein each circuit is a repeater circuit of a hub adapter card.
Claim 24
Dependent Claim
42 words
The system of claim 19 wherein said identity apparatus comprises a plurality of connectors, more than one connector being coupled to an electrical device such that each coupled connector indicates an identity different from the identity indicated by any other coupled connector.
Claim 25
Dependent Claim
116 words
The system of claim 19: wherein said identity apparatus comprises a plurality of connectors, each connector having apparatus terminals arranged symmetric with respect to each other; wherein said identity apparatus is spatially located with respect to a location of said plurality of electrical devices such that said connectors indicate a plurality of identities in a first sequence, each identity in said first sequence being different from every other identity in said first sequence; and further wherein said plurality of connectors indicate a second sequence of identities, said second sequence being in the reverse order of said first sequence when said identity apparatus is spatially reversed with respect to said location of said plurality of electrical devices.
Claim 26
Dependent Claim
23 words
The system of claim 19, wherein said apparatus terminals and a plurality of terminals of said bus are included in a single connector.
Claim 27
Dependent Claim
23 words
The system of claim 23, wherein said connector is one of a plurality of connectors of a system board included in said system.
Claim 28
Dependent Claim
22 words
The system of claim 23, wherein said connector is one of a plurality of connectors of a cable included in said system.
Claim 29
Dependent Claim
376 words
An electrical device comprising: a first circuit having a plurality of lines; a second circuit having a plurality of terminals including a group of device terminals and a group of internal terminals, each internal terminal being coupled to a line of said first circuit, each device terminal being coupled to a bus external to said electrical device, wherein said second circuit drives a signal active on an internal terminal in response to an active signal on another internal terminal and in absence of an active signal on any of said device terminals; and an identity cable having a left end and a right end, said cable comprising: a plurality of cable connectors a left cable connector of said plurality of cable connectors being located at said left end, a right cable connector of said plurality of cable connectors being located at said right end, each of said cable connectors comprising a plurality of cable terminals, at least one of said cable terminals being predetermined to be coupled to a device terminal in each of said electrical devices, said device terminal supplying a first signal at a predetermined first voltage level; a plurality of electrical conductors comprising said bus, each electrical conductor being flexible, each electrical conductor being insulated from another electrical conductor, at least one electrical conductor being connected to said predetermined cable terminal each of said cable connectors; wherein: at least two cable terminals in one of said plurality of cable connectors are coupled to each other such that appearance of said first signal on one of said two cable terminals indicates an identity of one of said electrical devices, and said cable terminals in each connector are arranged symmetric with respect to each other; said identity cable is spatially located and connected to said plurality of electrical devices in a first orientation such that said cable connectors indicate a plurality of identities in a first sequence, each identity in said first sequence being different from every other identity in said first sequence; and said plurality of cable connectors indicate a second sequence of identities, said second sequence being in the reverse order of said first sequence when said identity cable is connected in a second orientation spatially reversed with respect to said first orientation.
Claim 30
Dependent Claim
376 words
An electrical device comprising: a first circuit having a plurality of lines; a second circuit having a plurality of terminals including a group of device terminals and a group of internal terminals, each internal terminal being coupled to a line of said first circuit, each device terminal being coupled to a bus external to said electrical device, wherein said second circuit drives a signal active on an internal terminal in response to an active signal on another internal terminal and in absence of an active signal on any of said device terminals; and an identity cable having a left end and a right end, said cable comprising: a plurality of cable connectors a left cable connector of said plurality of cable connectors being located at said left end, a right cable connector of said plurality of cable connectors being located at said right end, each of said cable connectors comprising a plurality of cable terminals, at least one of said cable terminals being predetermined to be coupled to a device terminal in each of said electrical devices, said device terminal supplying a first signal at a predetermined first voltage level; a plurality of electrical conductors comprising said bus, each electrical conductor being flexible, each electrical conductor being insulated from another electrical conductor, at least one electrical conductor being connected to said predetermined cable terminal each of said cable connectors; wherein: at least two cable terminals in one of said plurality of cable connectors are coupled to each other such that appearance of said first signal on one of said two cable terminals indicates an identity of one of said electrical devices, and said cable terminals in each connector are arranged symmetric with respect to each other; said identity cable is spatially located and connected to said plurality of electrical devices in a first orientation such that said cable connectors indicate a plurality of identities in a first sequence, each identity in said first sequence being different from every other identity in said first sequence; and said plurality of cable connectors indicate a second sequence of identities, said second sequence being in the reverse order of said first sequence when said identity cable is connected in a second orientation spatially reversed with respect to said first orientation.
Claim 31
Dependent Claim
49 words
The system of claim 26, wherein: said first circuit includes a repeater circuit coupled to said second circuit; and in response to said active signal on said another internal terminal and an active signal on any device terminal said second circuit drives a signal active to said repeater circuit.
Claim 32
Dependent Claim
16 words
The electrical device of claim 26 wherein said first circuit is included in an integrated circuit.
Claim 33
Dependent Claim
17 words
The electrical device of claim 26 wherein said second circuit is included in a programmable logic device.
Claim 34
Dependent Claim
22 words
The electrical device of claim 26 wherein said first circuit and said second circuit are both included in a single integrated circuit.
Claim 35
Dependent Claim
25 words
The electrical device of claim 26 further comprising a user configurable element, wherein one of said device terminals is coupled to said user configurable element.
Claim 36
Dependent Claim
14 words
The electrical device of claim 31 wherein said user configurable element is a jumper.
Claim 37
Dependent Claim
21 words
The electrical device of claim 31 wherein said user configurable element is coupled to a voltage source in said electrical device.
Claim 38
Independent Claim
206 words
A system comprising: a plurality of electrical devices, each electrical device comprising a plurality of device terminals, at least one of said device terminals being an identity terminal, wherein a signal on one or more identity terminals indicates a unique identity to said electrical device; and an identity apparatus comprising a housing and a connector supported by said housing, said connector comprising a plurality of apparatus terminals, wherein when one of said electrical devices is coupled to said connector: a first apparatus terminal of said plurality of apparatus terminals is coupled to a first device terminal in said electrical device, said first apparatus terminal carrying a first signal supplied at said first device terminal, said first signal having an approximately fixed predetermined first voltage level; and a second apparatus terminal of said plurality of apparatus terminals is coupled to a second device terminal in said electrical device, said second device terminal being an identity terminal, wherein said first apparatus terminal is coupled inside said identity apparatus to said second apparatus terminal, and appearance of said first signal on said identity terminal indicates an identity of said electrical device different from an identity of said electrical device on appearance of a second signal on said identity terminal.
Claim 39
Independent Claim
206 words
A system comprising: a plurality of electrical devices, each electrical device comprising a plurality of device terminals, at least one of said device terminals being an identity terminal, wherein a signal on one or more identity terminals indicates a unique identity to said electrical device; and an identity apparatus comprising a housing and a connector supported by said housing, said connector comprising a plurality of apparatus terminals, wherein when one of said electrical devices is coupled to said connector: a first apparatus terminal of said plurality of apparatus terminals is coupled to a first device terminal in said electrical device, said first apparatus terminal carrying a first signal supplied at said first device terminal, said first signal having an approximately fixed predetermined first voltage level; and a second apparatus terminal of said plurality of apparatus terminals is coupled to a second device terminal in said electrical device, said second device terminal being an identity terminal, wherein said first apparatus terminal is coupled inside said identity apparatus to said second apparatus terminal, and appearance of said first signal on said identity terminal indicates an identity of said electrical device different from an identity of said electrical device on appearance of a second signal on said identity terminal.
Claim 40
Dependent Claim
17 words
The system of claim 34 wherein each circuit is a repeater circuit of a hub adapter card.
Claim 41
Dependent Claim
40 words
The system of claim 34 wherein said second apparatus terminal carries a ground reference signal supplied at said second device terminal in the absence of coupling inside said identity apparatus between said first apparatus terminal and said second apparatus terminal.
Claim 42
Dependent Claim
42 words
The system of claim 34 wherein said identity apparatus comprises a plurality of connectors, more than one connector being coupled to an electrical device such that each coupled connector indicates an identity different from the identity indicated by any other coupled connector.
Claim 43
Dependent Claim
116 words
The system of claim 34: wherein said identity apparatus comprises a plurality of connectors, each connector having apparatus terminals arranged symmetric with respect to each other; wherein said identity apparatus is spatially located with respect to a location of said plurality of electrical devices such that said connectors indicate a plurality of identities in a first sequence, each identity in said first sequence being different from every other identity in said first sequence; and further wherein said plurality of connectors indicate a second sequence of identities, said second sequence being in the reverse order of said first sequence when said identity apparatus is spatially reversed with respect to said location of said plurality of electrical devices.
Claim 44
Dependent Claim
44 words
The system of claim 34 wherein: said housing is a flexible tubular sheath and said plurality of apparatus terminals are connected to wires flexibly enclosed by said sheath to form a cable; and said cable has a plurality of connectors identical to said connector.
Claim 45
Dependent Claim
45 words
The system of claim 34 wherein; said housing is an inflexible system board and at least one apparatus terminal of said connector is connected to a voltage source in said system board; and said system board has a plurality of connectors identical to said connector.
Claim 46
Dependent Claim
24 words
The system of claim 34 wherein said first apparatus terminal is coupled through a pull-up resistor to a voltage source in said electrical device.
Claim 47
Dependent Claim
24 words
The system of claim 34 wherein said first apparatus terminal is coupled through a pull-up resistor to a voltage source in said identity apparatus.
Claim 48
Dependent Claim
26 words
The system of claim 34 further comprising a conductive link, said conductive link forming said coupling between said first apparatus terminal and said second apparatus terminal.
Claim 49
Dependent Claim
24 words
The system of claim 34 wherein said signal has an approximately fixed predetermined voltage level indicative of a logic state in said electrical device.
Claim 50
Dependent Claim
14 words
The system of claim 44 wherein said predetermined voltage level is the Vcc reference.
Claim 51
Dependent Claim
31 words
The system of claim 34 comprising a plurality of first apparatus terminals, wherein each unique combination of signals on said first apparatus terminals indicates a unique identity of said electrical device.
Claim 52
Independent Claim
281 words
A method for distributed arbitration of a resource shared by a plurality of electrical devices, each electrical device comprising a circuit having a local request line and an acknowledge line, said method comprising: providing an arbiter in each of said electrical devices, said arbiter comprising a local request terminal, an acknowledge terminal and a plurality of remote request terminals, said providing step comprising coupling said local request terminal to said local request line and coupling said acknowledge line to said acknowledge terminal coupled to said acknowledge line; causing said arbiter to drive a signal active on an acknowledge terminal in response to an active signal on said local request terminal and in absence of an active signal on any of said remote request terminals, wherein each electrical device comprises a plurality of device terminals, at least one of said device terminals being an identity terminal, wherein a signal .right brkt-top.. one or more identity terminals is capable of indicating a unique identity to said electrical device; supporting a first apparatus terminal and a second apparatus terminal in a connector of an identity apparatus such that said first apparatus terminal is coupled to a first predetermined device terminal in a first electrical device of said plurality of electrical devices and said second right terminal is coupled to a second predetermined device terminal in said first electrical device when said first electrical device is coupled to said connector; and coupling inside said connector said second apparatus terminal to said first apparatus terminal so that a signal supplied by said first electrical device to said first apparatus terminal can appear on said second apparatus terminal to indicate an identity of said first electrical device.
Claim 53
Independent Claim
281 words
A method for distributed arbitration of a resource shared by a plurality of electrical devices, each electrical device comprising a circuit having a local request line and an acknowledge line, said method comprising: providing an arbiter in each of said electrical devices, said arbiter comprising a local request terminal, an acknowledge terminal and a plurality of remote request terminals, said providing step comprising coupling said local request terminal to said local request line and coupling said acknowledge line to said acknowledge terminal coupled to said acknowledge line; causing said arbiter to drive a signal active on an acknowledge terminal in response to an active signal on said local request terminal and in absence of an active signal on any of said remote request terminals, wherein each electrical device comprises a plurality of device terminals, at least one of said device terminals being an identity terminal, wherein a signal .right brkt-top.. one or more identity terminals is capable of indicating a unique identity to said electrical device; supporting a first apparatus terminal and a second apparatus terminal in a connector of an identity apparatus such that said first apparatus terminal is coupled to a first predetermined device terminal in a first electrical device of said plurality of electrical devices and said second right terminal is coupled to a second predetermined device terminal in said first electrical device when said first electrical device is coupled to said connector; and coupling inside said connector said second apparatus terminal to said first apparatus terminal so that a signal supplied by said first electrical device to said first apparatus terminal can appear on said second apparatus terminal to indicate an identity of said first electrical device.
Claim 54
Dependent Claim
28 words
A method comprising the steps of claim 47 followed by: coupling said identity apparatus to said first electrical device; and supplying said signal to said first apparatus terminal.
Claim 55
Dependent Claim
53 words
The method of claim 47 wherein the arbiter has a collision terminal, the method further comprising: causing said arbiter to drive a signal active on said collision terminal in response to said active signal on said local request terminal and presence of an active signal on any remote request terminal of said arbiter.
Claim 56
Dependent Claim
21 words
The method of claim 49 further comprising: implementing a backoff algorithm in response to said active signal on said collision terminal.
Claim 57
Dependent Claim
17 words
The method of claim 47 further comprising: supplying a clock signal to each of said electrical devices.
Claim 58
Dependent Claim
39 words
The method of claim 51 further comprising: using a user configurable element in each of said electrical devices to identify one of said electrical devices as a master electrical device, wherein said master electrical device supplies said clock signal.
Claim 59
Dependent Claim
21 words
The method of claim 47 further comprising: using said central resource in response to said active signal on said acknowledge terminal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-05-18 | 2001-11-17 | 2002-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-05-18 | 2005-11-17 | 2006-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-05-18 | 2009-11-17 | 2010-05-19 | $7700.00 | Window Closed / Lapsed |