US5467453A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit for providing automatic SCSI bus termination
Assignee: Dell USA LP
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Filing: 1993-07-20
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Granted: 1995-11-14
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Expires: 2013-07-20
Abstract
Abstract Disclosed are a circuit and method for providing automatic termination for a small computer systems interface ("SCSI") bus. The circuit resides within a bus controller comprising (1) a control circuit for controlling transmission of data on a bus and for providing an interface between the bus and a computer system for communication of the data therebetween and (2) a first bus port and a second bus port, each of the first and second bus ports permitting a device to be coupled thereto for communication with the control circuit via the bus, the bus controller being at an end of the bus when a single one of the first and second bus ports is coupled to a device and being in a middle of the bus when both the first and second bus ports are coupled to devices. The circuit of the present invention is coupled to the first and second bus ports and is capable of coupling a terminating circuit to the bus as a function of a presence of devices coupled to the first and second bus ports, the bus requiring coupling of the terminating circuit when the bus controller is at the end of the bus.
Inventors
- 👤 Thomas Kocis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:21
CPC Classifications
G; G06; G06F; G06F13/00; G06F13/38; G06F13/40; G06F13/4063; G06F13/4068; G06F13/4086
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
171 words
A bus controller, comprising: a control circuit for controlling transmission of data on a bus and for providing an interface between said bus and a computer system for communication of said data therebetween; a first bus port and a second bus port, each of said first and second bus ports permitting a device to be coupled thereto for communication with said control circuit via said bus, said bus controller being at an end of said bus when a single one of said first and second bus ports is coupled to a device and being in a middle of said bus when both said first and second bus ports are coupled to devices; and an automatic bus termination circuit coupled to said first and second bus ports and capable of coupling a terminating circuit to said bus as a function of a presence of devices coupled to said first and second bus ports, said bus requiring coupling of said terminating circuit when said bus controller is at said end of said bus.
Claim 2
Dependent Claim
171 words
A bus controller, comprising: a control circuit for controlling transmission of data on a bus and for providing an interface between said bus and a computer system for communication of said data therebetween; a first bus port and a second bus port, each of said first and second bus ports permitting a device to be coupled thereto for communication with said control circuit via said bus, said bus controller being at an end of said bus when a single one of said first and second bus ports is coupled to a device and being in a middle of said bus when both said first and second bus ports are coupled to devices; and an automatic bus termination circuit coupled to said first and second bus ports and capable of coupling a terminating circuit to said bus as a function of a presence of devices coupled to said first and second bus ports, said bus requiring coupling of said terminating circuit when said bus controller is at said end of said bus.
Claim 3
Dependent Claim
18 words
The controller as recited in claim 1 wherein said bus is a small computer systems interface (SCSI) bus.
Claim 4
Dependent Claim
45 words
The controller as recited in claim 1 wherein said automatic bus termination circuit is capable of determining a presence of devices coupled to said first and second bus ports by measuring a voltage of a pin within each of said first and second bus ports.
Claim 5
Dependent Claim
37 words
The controller as recited in claim 1 wherein said automatic bus termination circuit impresses a voltage on a pin within each of said first and second bus ports, said voltage removed when a device is coupled thereto.
Claim 6
Dependent Claim
50 words
The controller as recited in claim 1 wherein said automatic bus termination circuit uses a pin within each of said first and second bus ports to determine said presence, said automatic bus termination circuit returning said pin to a normal bus function following operation of said automatic bus termination circuit.
Claim 7
Dependent Claim
20 words
The controller as recited in claim 1 wherein a bus setup signal triggers operation of said automatic bus termination circuit.
Claim 8
Dependent Claim
18 words
The controller as recited in claim 1 wherein said terminating circuit reduces ringing of signals on said bus.
Claim 9
Dependent Claim
15 words
The controller as recited in claim 1 wherein said computer system is a personal computer.
Claim 10
Independent Claim
184 words
A method of automatically terminating a bus at a bus controller, comprising the steps of: controlling transmission of data on a bus with a control circuit, said control circuit providing an interface between said bus and a computer system for communication of said data therebetween; allowing devices to be coupled to a first bus port and a second bus port, each of said first and second bus ports permitting devices coupled thereto to communicate with said control circuit via said bus, said bus controller being at an end of said bus when a single one of said first and second bus ports is coupled to a device and being in a middle of said bus when both said first and second bus ports are coupled to devices; and coupling a terminating circuit to said bus as a function of a presence of devices coupled to said first and second bus ports with an automatic bus termination circuit coupled to said first and second bus ports, said bus requiring coupling of said terminating circuit when said bus controller is at said end of said bus.
Claim 11
Independent Claim
184 words
A method of automatically terminating a bus at a bus controller, comprising the steps of: controlling transmission of data on a bus with a control circuit, said control circuit providing an interface between said bus and a computer system for communication of said data therebetween; allowing devices to be coupled to a first bus port and a second bus port, each of said first and second bus ports permitting devices coupled thereto to communicate with said control circuit via said bus, said bus controller being at an end of said bus when a single one of said first and second bus ports is coupled to a device and being in a middle of said bus when both said first and second bus ports are coupled to devices; and coupling a terminating circuit to said bus as a function of a presence of devices coupled to said first and second bus ports with an automatic bus termination circuit coupled to said first and second bus ports, said bus requiring coupling of said terminating circuit when said bus controller is at said end of said bus.
Claim 12
Dependent Claim
18 words
The method as recited in claim 9 wherein said bus is a small computer systems interface (SCSI) bus.
Claim 13
Dependent Claim
47 words
The method as recited in claim 9 further comprising the step of determining, with said automatic bus termination circuit, a presence of devices coupled to said first and second bus ports by measuring a voltage of a pin within each of said first and second bus ports.
Claim 14
Dependent Claim
43 words
The method as recited in claim 9 further comprising the step of impressing, with said automatic bus termination circuit, a voltage on a pin within each of said first and second bus ports, said voltage being removed when a device is coupled thereto.
Claim 15
Dependent Claim
55 words
The method as recited in claim 9 further comprising the step of using, with said automatic bus termination circuit, a pin within each of said first and second bus ports to determine said presence, said automatic bus termination circuit returning said pin to a normal bus function following operation of said automatic bus termination circuit.
Claim 16
Dependent Claim
25 words
The method as recited in claim 9 further comprising the step of triggering operation of said automatic bus termination circuit with a bus setup signal.
Claim 17
Dependent Claim
18 words
The method as recited in claim 9 wherein said terminating circuit reduces ringing of signals on said bus.
Claim 18
Dependent Claim
15 words
The method as recited in claim 9 wherein said computer system is a personal computer.
Claim 19
Dependent Claim
170 words
A controller for a small computer systems interface (SCSI) bus, comprising: an SCSI control circuit for controlling transmission of data on said SCSI bus and for providing an interface between said SCSI bus and a personal computer for communication of said data therebetween; a first SCSI port and a second SCSI port, each of said first and second SCSI ports permitting an SCSI device to be coupled thereto for communication with said SCSI control circuit via said SCSI bus, said controller being at an end of said SCSI bus when a single one of said first and second SCSI ports is coupled to an SCSI device and being in a middle of said SCSI bus when both said first and second SCSI ports are coupled to SCSI devices; and an automatic bus termination circuit coupled to said first and second SCSI ports and capable of coupling an SCSI bus terminator to said bus as a function of a presence of SCSI devices coupled to said first and second SCSI ports.
Claim 20
Dependent Claim
170 words
A controller for a small computer systems interface (SCSI) bus, comprising: an SCSI control circuit for controlling transmission of data on said SCSI bus and for providing an interface between said SCSI bus and a personal computer for communication of said data therebetween; a first SCSI port and a second SCSI port, each of said first and second SCSI ports permitting an SCSI device to be coupled thereto for communication with said SCSI control circuit via said SCSI bus, said controller being at an end of said SCSI bus when a single one of said first and second SCSI ports is coupled to an SCSI device and being in a middle of said SCSI bus when both said first and second SCSI ports are coupled to SCSI devices; and an automatic bus termination circuit coupled to said first and second SCSI ports and capable of coupling an SCSI bus terminator to said bus as a function of a presence of SCSI devices coupled to said first and second SCSI ports.
Claim 21
Dependent Claim
46 words
The controller as recited in claim 17 wherein said automatic bus termination circuit is capable of determining a presence of SCSI devices coupled to said first and second SCSI ports by measuring a voltage of a pin within each of said first and second SCSI ports.
Claim 22
Dependent Claim
38 words
The controller as recited in claim 17 wherein said automatic bus termination circuit impresses a voltage on a pin within each of said first and second SCSI ports, said voltage removed when an SCSI device is coupled thereto.
Claim 23
Dependent Claim
51 words
The controller as recited in claim 17 wherein said automatic bus termination circuit uses a pin within each of said first and second SCSI ports to determine said presence, said automatic bus termination circuit returning said pin to a normal SCSI bus function following operation of said automatic bus termination circuit.
Claim 24
Dependent Claim
21 words
The controller as recited in claim 17 wherein an SCSI bus setup signal triggers operation of said automatic bus termination circuit.
Claim 25
Dependent Claim
19 words
The controller as recited in claim 17 wherein said SCSI terminator reduces ringing of signals on said SCSI bus.
Claim 26
Independent Claim
181 words
A method of terminating a small computer systems interface (SCSI) bus at an SCSI controller, comprising the steps of: controlling transmission of data on an SCSI bus with an SCSI control circuit, said SCSI control circuit providing an interface between said bus and a personal computer for communication of said data therebetween; allowing SCSI devices to be coupled to a first SCSI port and a second SCSI port, each of said first and second SCSI ports permitting devices coupled thereto to communicate with said SCSI control circuit via said SCSI bus, said SCSI controller being at an end of said SCSI bus when a single one of said first and second SCSI ports is coupled to a SCSI device and being in a middle of said SCSI bus when both said first and second SCSI ports are coupled to SCSI devices; and coupling an SCSI terminator to said SCSI bus as a function of a presence of SCSI devices coupled to said first and second SCSI ports with an automatic bus termination circuit coupled to said first and second SCSI ports.
Claim 27
Independent Claim
181 words
A method of terminating a small computer systems interface (SCSI) bus at an SCSI controller, comprising the steps of: controlling transmission of data on an SCSI bus with an SCSI control circuit, said SCSI control circuit providing an interface between said bus and a personal computer for communication of said data therebetween; allowing SCSI devices to be coupled to a first SCSI port and a second SCSI port, each of said first and second SCSI ports permitting devices coupled thereto to communicate with said SCSI control circuit via said SCSI bus, said SCSI controller being at an end of said SCSI bus when a single one of said first and second SCSI ports is coupled to a SCSI device and being in a middle of said SCSI bus when both said first and second SCSI ports are coupled to SCSI devices; and coupling an SCSI terminator to said SCSI bus as a function of a presence of SCSI devices coupled to said first and second SCSI ports with an automatic bus termination circuit coupled to said first and second SCSI ports.
Claim 28
Dependent Claim
48 words
The method as recited in claim 23 further comprising the step of determining, with said automatic bus termination circuit, a presence of SCSI devices coupled to said first and second SCSI ports by measuring a voltage of a pin within each of said first and second SCSI ports.
Claim 29
Dependent Claim
44 words
The method as recited in claim 23 further comprising the step of impressing, with said automatic bus termination circuit, a voltage on a pin within each of said first and second SCSI ports, said voltage being removed when an SCSI device is coupled thereto.
Claim 30
Dependent Claim
56 words
The method as recited in claim 23 further comprising the step of using, with said automatic bus termination circuit, a pin within each of said first and second SCSI ports to determine said presence, said automatic bus termination circuit returning said pin to a normal SCSI bus function following operation of said automatic bus termination circuit.
Claim 31
Dependent Claim
26 words
The method as recited in claim 23 further comprising the step of triggering operation of said automatic bus termination circuit with an SCSI bus setup signal.
Claim 32
Dependent Claim
19 words
The method as recited in claim 23 wherein said SCSI terminator reduces ringing of signals on said SCSI bus.
Claim 33
Dependent Claim
161 words
A circuit for providing automatic small computer systems interface (SCSI) bus termination, comprising: a first circuit for placing a first selected pin in a first SCSI bus port at a first selected voltage, said first selected voltage being changed when a first SCSI device is coupled to said first SCSI bus port; a second circuit for placing a second selected pin in a second SCSI bus port at a second selected voltage, said second selected voltage being changed when a second SCSI device is coupled to said second SCSI bus port, an SCSI bus coupled between said first and second SCSI bus ports for communication of data therebetween; and a termination control circuit capable of determining whether said first and second selected voltages are changed and for coupling an SCSI terminator to said SCSI bus when only one of said first and second voltages is changed, said coupling signifying that said SCSI terminator is at an end of said SCSI bus.
Claim 34
Dependent Claim
161 words
A circuit for providing automatic small computer systems interface (SCSI) bus termination, comprising: a first circuit for placing a first selected pin in a first SCSI bus port at a first selected voltage, said first selected voltage being changed when a first SCSI device is coupled to said first SCSI bus port; a second circuit for placing a second selected pin in a second SCSI bus port at a second selected voltage, said second selected voltage being changed when a second SCSI device is coupled to said second SCSI bus port, an SCSI bus coupled between said first and second SCSI bus ports for communication of data therebetween; and a termination control circuit capable of determining whether said first and second selected voltages are changed and for coupling an SCSI terminator to said SCSI bus when only one of said first and second voltages is changed, said coupling signifying that said SCSI terminator is at an end of said SCSI bus.
Claim 35
Dependent Claim
33 words
The circuit as recited in claim 29 wherein said termination control circuit returns said first and second selected pins to a normal SCSI bus function following operation of said automatic bus termination circuit.
Claim 36
Dependent Claim
20 words
The circuit as recited in claim 29 wherein an SCSI bus setup signal triggers operation of said termination control circuit.
Claim 37
Dependent Claim
19 words
The circuit as recited in claim 29 wherein said SCSI terminator reduces ringing of signals on said SCSI bus.
Claim 38
Independent Claim
155 words
A method of providing automatic SCSI bus termination, comprising: placing a first selected pin in a first SCSI bus port at a first selected voltage with a first circuit, said first selected voltage being changed when a first SCSI device is coupled to said first SCSI bus port; placing a second selected pin in a second SCSI bus port at a second selected voltage with a second circuit, said second selected voltage being changed when a second SCSI device is coupled to said second SCSI bus port, an SCSI bus coupled between said first and second SCSI bus ports for communication of data therebetween; and determining, with a termination control circuit, whether said first and second selected voltages are changed; and coupling an SCSI terminator to said SCSI bus when only one of said first and second voltages is changed, said coupling signifying that said SCSI terminator is at an end of said SCSI bus.
Claim 39
Independent Claim
155 words
A method of providing automatic SCSI bus termination, comprising: placing a first selected pin in a first SCSI bus port at a first selected voltage with a first circuit, said first selected voltage being changed when a first SCSI device is coupled to said first SCSI bus port; placing a second selected pin in a second SCSI bus port at a second selected voltage with a second circuit, said second selected voltage being changed when a second SCSI device is coupled to said second SCSI bus port, an SCSI bus coupled between said first and second SCSI bus ports for communication of data therebetween; and determining, with a termination control circuit, whether said first and second selected voltages are changed; and coupling an SCSI terminator to said SCSI bus when only one of said first and second voltages is changed, said coupling signifying that said SCSI terminator is at an end of said SCSI bus.
Claim 40
Dependent Claim
38 words
The method as recited in claim 33 further comprising the step of returning, with said termination control circuit, said first and second selected pins to a normal SCSI bus function following operation of said automatic bus termination method.
Claim 41
Dependent Claim
25 words
The method as recited in claim 33 further comprising the step of triggering, with an SCSI bus setup signal, operation of said termination control circuit.
Claim 42
Dependent Claim
19 words
The method as recited in claim 33 wherein said SCSI terminator reduces ringing of signals on said SCSI bus.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-11-13 | 1999-05-15 | 1999-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-11-13 | 2003-05-15 | 2003-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-11-13 | 2007-05-15 | 2007-11-14 | $7700.00 | Window Closed / Lapsed |