US4839852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Programmable controller with self testing I/O structure
Assignee: Allen Bradley Co LLC
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Filing: 1988-06-16
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Granted: 1989-06-13
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Expires: 2008-06-16
Abstract
Abstract A programmable controller includes a processor unit which connects to one or more I/O units that connect to sensing devices and operating devices on equipment being controlled. When placed in the RUN mode, the processor determines the number of I/O units required to execute the user control program, and during each subsequent I/O scan, the number of connected and operating I/O units is checked to insure proper operation.
Inventors
- 👤 Neil W. Knutsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:52
CPC Classifications
G; G05; G05B; G05B19/00; G05B19/02; G05B19/04; G05B19/05; G05B19/058; G05B2219/00; G05B2219/10; G05B2219/13; G05B2219/13193
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
225 words
In a programmable controller having a processor unit which may be connected to one or more I/O expansion units, the combination comprising: storage means in said processor unit for storing a user control program which includes instructions that direct the examination of input devices connected to I/O expansion units and instructions that direct the operation of output devices connected to I/O expansion units; examination means coupled to the storage means for examining the user control program instructions and determining a highest number in a number range of the I/O expansion untis which are required to execute the user control program; scanner means responsive to signals from the I/O expansion units for determining a number range of I/O expansion units which are connected to the processor unit; comparison means coupled to the examination means and the scanner means for comparing a highest number in the number range of the I/O expansion units determined by the scanner means with the highest number in the number range of I/O expansion units determined by the examination means; and means responsive to said comparison means for preventing execution of the user control program when the highest number in the number range of the I/O expansion units determined by the scanner means does not match the highest number in the number range of I/O expansion units determined by the examination means.
Claim 2
Dependent Claim
225 words
In a programmable controller having a processor unit which may be connected to one or more I/O expansion units, the combination comprising: storage means in said processor unit for storing a user control program which includes instructions that direct the examination of input devices connected to I/O expansion units and instructions that direct the operation of output devices connected to I/O expansion units; examination means coupled to the storage means for examining the user control program instructions and determining a highest number in a number range of the I/O expansion untis which are required to execute the user control program; scanner means responsive to signals from the I/O expansion units for determining a number range of I/O expansion units which are connected to the processor unit; comparison means coupled to the examination means and the scanner means for comparing a highest number in the number range of the I/O expansion units determined by the scanner means with the highest number in the number range of I/O expansion units determined by the examination means; and means responsive to said comparison means for preventing execution of the user control program when the highest number in the number range of the I/O expansion units determined by the scanner means does not match the highest number in the number range of I/O expansion units determined by the examination means.
Claim 3
Dependent Claim
65 words
The programmable controller as recited in claim 1 in which the processor unit operates in a programming mode in which the user control program may be created or changed using a programming unit; and the examination means, scanner means and comparison means operate each time the processor unit is switched to a RUN mode in which it is to repeatedly execute the user control program.
Claim 4
Dependent Claim
46 words
The programmable controller as recited in claim 1 in which the examination means includes means for outputting a check bit to I/O units connected to the processor unit, and means for inputting said check bit from the I/O units which are attached to the processor unit.
Claim 5
Dependent Claim
200 words
In a programmable controller having a processor unit which may be connected to one or more I/O expansion units, the combination comprising: storage means in said processor unit for storing a user control program which includes instructions that direct the examination of input devices connected to I/O expansion units and instructions that direct the operation of output devices connected to I/O expansion units; examination means coupled to the storage means for examining the user control program instructions and determining addresses of the I/O expansion units which are required to execute the user control program; scanner means responsive to signals from the I/O expansion units for determining addresses of I/O expansion units which are connected to the processor unit; and comparison means coupled to the examination means and the scanner means for comparing the addresses of the I/O expansion units determined by the examination means with the addresses of I/O expansion units determined by the scanner means; and means responsive to said comparison means for preventing execution of the user control program when the address of the I/O expansion unit determined by the examination means is not one of the addresses of the I/O expansion units determined by the scanner means.
Claim 6
Dependent Claim
200 words
In a programmable controller having a processor unit which may be connected to one or more I/O expansion units, the combination comprising: storage means in said processor unit for storing a user control program which includes instructions that direct the examination of input devices connected to I/O expansion units and instructions that direct the operation of output devices connected to I/O expansion units; examination means coupled to the storage means for examining the user control program instructions and determining addresses of the I/O expansion units which are required to execute the user control program; scanner means responsive to signals from the I/O expansion units for determining addresses of I/O expansion units which are connected to the processor unit; and comparison means coupled to the examination means and the scanner means for comparing the addresses of the I/O expansion units determined by the examination means with the addresses of I/O expansion units determined by the scanner means; and means responsive to said comparison means for preventing execution of the user control program when the address of the I/O expansion unit determined by the examination means is not one of the addresses of the I/O expansion units determined by the scanner means.
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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) | 1992-06-12 | 1992-12-12 | 1993-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-12 | 1996-12-12 | 1997-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-12 | 2000-12-12 | 2001-06-13 | $7700.00 | Window Closed / Lapsed |