US5070501A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Token passing type slotted loop network system with means for enabling high speed access control and simple frame slot stripping
Assignee: NEC Corp
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Filing: 1990-06-11
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Granted: 1991-12-03
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Expires: 2010-06-11
Abstract
Abstract A token passing slotted loop network comprising a master station and a plurality of slave stations, a plurality of slots circulating through the loop and each of the slots having a fixed length and comprising a header portion and a data carrier portion, a particular one of the stations having the token transmitting its own data signal by use of one or more of the slots, the particular station transmits an end mark in the header of a particular one of the slots at an end of transmission of the own data signal and strips incoming slots from a start of the transmission of the own data signal unit reception of the end mark circulated through the loop. The particular station frees the token by inserting the token in the header of the particular slot. The token can be inserted in the header of one of the slots after completion of the transmission. Each of the slave stations writes into a priority request section in the header of each slot a particularly priority request representative of a priority level of the own data signal when the own data signal occurs thereat. The master station writes the highest one of the priority request into a priority section in the header of each slot. Each slave station detects the priority in the priority section and starts to acquire the token when the detected priority is lower than the particular priority request.
Inventors
- 👤 Hiroshi Shimizu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:10
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/28; H04L12/42; H04L12/427; H04L12/433; H04Q; H04Q11/00; H04Q11/04; H04Q11/0428; H04Q11/0478; H04L12/54; H04L12/56; H04L12/5601; H04L2012/5614; H04L2012/5615; H04L2012/5616; H04L2012/5638; H04L2012/5646
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
358 words
A token passing type slotted loop network system comprising a master node station and a plurality of slave node stations connected to each other to form a data transmission loop, a plurality of slots being circulated on said loop for transmitting a data signal from a particular one of the node stations having the token, each of said slots having a fixed length and comprising: a header portion comprising an end/non-end code section for carrying the end/non-end code, the end code and the non-end code representing an end and a non-end of transmission of the data signal; and a data carrier portion for carrying the data signal, each of said master and slave node stations comprising: multiplexing means for multiplexing input signals applied thereto to produce a multiplexed signal, said multiplexed signal being delivered therefrom to said loop; transmissions buffer means for holding the data signal to be transmitted to said loop as a buffered data signal as one of said slots; demultiplexing means for demultiplexing each of said slots sequentially incoming thereto as an incoming slot signal to produce said end/non-end code section and said data carrier portion of said incoming slot signal as a separated end/non-end signal and a separated data signal; selecting means coupled to said demultiplexing means and said transmission buffer means for selecting said separated data signal at a repeating mode and said buffered data signal at a transmission mode as a selected signal, said selected signal being delivered to said multiplexing means as one of said input signals; end-mark processing means coupled to said demultiplexing means for repeating said separated end/non-end signal to said multiplexing means as another one of said input signals at a repeating mode, said end-mark processing means producing a non-end code signal and an end code signal to deliver the non-end code signal and the end code signal to said multiplexing means as another one of said input signals at a non-end condition and an end condition, respectively; and control means coupled to said demultiplexing means, said transmission buffer means, said selecting means and said end-mark processing means for controlling said end-mark processing means and said selecting means.
Claim 2
Dependent Claim
358 words
A token passing type slotted loop network system comprising a master node station and a plurality of slave node stations connected to each other to form a data transmission loop, a plurality of slots being circulated on said loop for transmitting a data signal from a particular one of the node stations having the token, each of said slots having a fixed length and comprising: a header portion comprising an end/non-end code section for carrying the end/non-end code, the end code and the non-end code representing an end and a non-end of transmission of the data signal; and a data carrier portion for carrying the data signal, each of said master and slave node stations comprising: multiplexing means for multiplexing input signals applied thereto to produce a multiplexed signal, said multiplexed signal being delivered therefrom to said loop; transmissions buffer means for holding the data signal to be transmitted to said loop as a buffered data signal as one of said slots; demultiplexing means for demultiplexing each of said slots sequentially incoming thereto as an incoming slot signal to produce said end/non-end code section and said data carrier portion of said incoming slot signal as a separated end/non-end signal and a separated data signal; selecting means coupled to said demultiplexing means and said transmission buffer means for selecting said separated data signal at a repeating mode and said buffered data signal at a transmission mode as a selected signal, said selected signal being delivered to said multiplexing means as one of said input signals; end-mark processing means coupled to said demultiplexing means for repeating said separated end/non-end signal to said multiplexing means as another one of said input signals at a repeating mode, said end-mark processing means producing a non-end code signal and an end code signal to deliver the non-end code signal and the end code signal to said multiplexing means as another one of said input signals at a non-end condition and an end condition, respectively; and control means coupled to said demultiplexing means, said transmission buffer means, said selecting means and said end-mark processing means for controlling said end-mark processing means and said selecting means.
Claim 3
Dependent Claim
150 words
A token passing slotted loop network as claimed in claim 1, wherein, in said particular node station, said control means makes said end-mark processing means and said selecting means be in said non-end condition and in said transmission mode, respectively, said control means monitoring said transmission buffer means and making said end-mark processing means be in said end condition to produce said end code signal at an end of transmission of said buffered data signal, said control means making said end-mark processing means and said selecting means be in said repeating condition and in said repeating mode, respectively, when said control means detects that said demultiplexed end/non-end signal is said end code signal, and wherein, in each of the node stations other than said particular node station, said control means makes said end-mark processing means and said selecting means be in said repeating condition and in said repeating mode, respectively.
Claim 4
Dependent Claim
146 words
A token passing slotted loop network as claimed in claim 2, wherein said header portion further comprises a token/non/token code section for carrying one of a token code representing the token and a non-token code, said demultiplexing means separating said token/non-token code section from said incoming slot signal to produce a separated token/non-token signal, and wherein each of said master and said slave node stations further comprises token processing means coupled to said demultiplexing means for repeating said separated token/non-token signal to said multiplexing means as another one of said input signals at a repeating condition, said token processing means producing the non-token code signal and the token code signal to deliver the non-token code signal and the token code signal at a non-token condition and a token condition, respectively, to said multiplexing means as another input signal, said control means controlling said token/non-token processing means.
Claim 5
Dependent Claim
92 words
A token passing slotted loop network as claimed in claim 3, wherein said control means makes said token processing means be in said non-token condition in order to acquire the token when detecting that said transmission buffer means holds said buffered data signal, said control means acquiring the token when detecting that said separated token/non-token signal is said token code signal, and said control means, as said control means in said particular node station, making said end-mark processing means and said selecting means be in said non-end condition and said transmission mode.
Claim 6
Dependent Claim
57 words
A token passing slotted loop network as claimed in claim 4, wherein, in said particular node station, said control means makes said token processing means be in said token condition so as to free the token at the end of transmission of said buffered data signal and then makes said token processing means into said repeating condition.
Claim 7
Dependent Claim
161 words
A token passing slotted loop network as claimed in claim 4, said data signal having a priority of one of different priority levels from a minimum level to a maximum level, wherein said header portion further comprises a priority request section for carrying a priority request representing a priority level requested at each of said slave node stations, and a priority section for carrying the highest priority level in said priority request as an indication priority level, said demultiplexing means separating said priority request section from said incoming slot signal as a separated priority request, and wherein said master node station further comprises priority control means coupled to said demultiplexing means responsive to said separated priority request for detecting the highest priority level in said separated priority request as a detected priority level to set said detected priority level in said priority section as said indication priority level, said priority control means setting the minimum level in said priority request section.
Claim 8
Dependent Claim
123 words
A token passing type slotted loop network as claimed in claim 6, said control means in each of said slave node stations monitoring said transmission buffer means to detect a particular one of the priority levels requested by said buffered data signal in said transmission buffer means as a particular priority request, wherein each of said slave node stations further comprises priority register means coupled to said control means for holding said particular priority request; and priority request processing means coupled to said demultiplexing means and said priority register means for producing a specific priority request from said particular priority request and said separated priority request to deliver said specific priority request as another one of said input signals to said multiplexing means.
Claim 9
Dependent Claim
114 words
A token passing type slotted loop network system as claimed in claim 7, wherein, in each of said slave node station, said demultiplexing means demultiplexes said priority section in said incoming slot signal as a separated priority signal, said separated priority signal being delivered as another of said input signals to said multiplexing means, said control means responsive to said separated priority signal for comparing said indication priority level of said separated priority signal with said particular priority request level, said control means making said token processing means be in said non-token condition when said particular priority request level is equal to or higher than said indication priority level of said separated priority signal.
Claim 10
Dependent Claim
97 words
A token passing type slotted loop network system as claimed in claim 7, said priority being divided into N (N being an integer) levels from said minimum level to said maximum level, said priority request being represented by a binary code of N digits with "1" in different digits representing different priority levels so that "1" of the highest and the lowest digits represents the maximum and the minimum levels, wherein said priority request processing means comprises means for writing "1" into a particular digit in said separated priority request signal corresponding to said particular priority request.
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) | 1994-12-02 | 1995-06-03 | 1995-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-02 | 1999-06-03 | 1999-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-02 | 2003-06-03 | 2003-12-03 | $7700.00 | Window Closed / Lapsed |