EP0239323A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
CPU channel to control unit extender
Assignee: ChannelNet Corp
•
Filing: 1987-03-19
•
Granted: —
•
Expires: 2007-03-19
Abstract
Abstract A system is described with which data can be reliably transferred at high channel speeds between an IBM CPU channel and a remotely located control unit through a high speed full duplex data link that can be a T3 speed telephone line. A pair of similar coupler units are provided, one of which is connected by way of conventional bus and tag cables to a channel and the other by such cables to the remotely located control unit. In one embodiment, the coupler units have extended buffers to enable retransmissions of entire data blocks in case of error. A special counter technique is described whereby the transfer of fixed length data blocks for i/0 devices such as printers can be accommodated without creating incorrect length problems with the channel. A high speed microprocessor is used to regulate the initialization and end sequences needed to establish communication between the channel and a control unit while a data transfer assist logic controls the transfer of data which is transmitted over the serial data link without interlock signals normally used between a channel and a control unit. A data streaming mode is accommodated.
Inventors
- 👤 Billy B. Waldron
- 👤 Ernest H. Wilson, Jr.
- 👤 Paul Yursis
- 👤 James B. Klingensmith
- 👤 Mathew Harris
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 19:55
CPC Classifications
G; G06; G06F; G06F13/00; G06F13/10; G06F13/12; G06F13/122; G06F11/00; G06F11/07; G06F11/14; G06F11/1402; G06F11/1415; G06F11/1443; G06F11/0703; G06F11/0751; G06F11/0754; G06F11/076; G06F11/08; G06F11/10
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
198 words
A system with which an IBM CPU channel located at one site can communicate at high channel speeds through a channel connected coupler unit, a serial bidirectional high speed data link and a control unit connected coupler unit with a control unit located at another site for data transfer with an I/O device, comprising: first and second coupler units for respective connection to the channel and the control unit, each coupler unit comprising: means in each coupler unit for generating initial selection and end sequence interlock signals respectively to either the connected channel or the connected control unit; means in each coupler unit for producing vectors for transmittal along the data link to activate local interlock signals from said generating means; means in each coupler unit for producing local interlock signals to either the connected channel or the connected control unit for the transfer of data therebetween at high channel speeds; and means in each coupler unit for transferring data bytes at high channel speeds between a connected channel or connected control unit and the serial data link for high channel speed data transfer without interlock signals between the channel and the control unit through said data link.
Claim 2
Independent Claim
198 words
A system with which an IBM CPU channel located at one site can communicate at high channel speeds through a channel connected coupler unit, a serial bidirectional high speed data link and a control unit connected coupler unit with a control unit located at another site for data transfer with an I/O device, comprising: first and second coupler units for respective connection to the channel and the control unit, each coupler unit comprising: means in each coupler unit for generating initial selection and end sequence interlock signals respectively to either the connected channel or the connected control unit; means in each coupler unit for producing vectors for transmittal along the data link to activate local interlock signals from said generating means; means in each coupler unit for producing local interlock signals to either the connected channel or the connected control unit for the transfer of data therebetween at high channel speeds; and means in each coupler unit for transferring data bytes at high channel speeds between a connected channel or connected control unit and the serial data link for high channel speed data transfer without interlock signals between the channel and the control unit through said data link.
Claim 3
Dependent Claim
59 words
A system as claimed in claim 1 wherein said coupler units further each have: buffer means for storing an entire block of data bytes to be transferred in response to an initial selection sequence; and means for retransmitting a said stored data block from one buffer means to the other buffer means in case of a data byte error.
Claim 4
Dependent Claim
59 words
A system as claimed in claim 2 and further including: means in a coupler unit for connection to a control unit for enabling its initial selection generating means when a said data block is received at the latter coupler unit without error and for transferring data from the buffer means to an I/O device connected to said control unit.
Claim 5
Independent Claim
66 words
A system as claimed in any one of the preceding claims wherein a coupler unit for connection to the channel includes: counter means for storing a count associated with a predetermined number of data bytes for an I/O device; and means responsive to said counter means in the coupler means for limiting the transfer of data from the channel to said predetermined number of data bytes.
Claim 6
Independent Claim
152 words
A system as claimed in any one of the preceding claims wherein the control unit is connected to an I/0 device that requires a fixed number of data bytes and wherein the coupler unit for connection to the channel has first counter means for counting the number of bytes transferred from a channel to the latter coupler unit; said coupler unit intended for connection to the control unit having second counting means for counting the number of bytes transferred from said coupler unit to the control unit; means for storing the count that is in said second counting means in said first counting means after the predetermined number of data bytes have been transferred to the I/O device to enable said channel to identify a correct data transfer to said I/O device in the event the counts in said first and second counter means were not the same during said initial transfer.
Claim 7
Independent Claim
71 words
A system as claimed in any one of the preceding claims wherein each coupler_unit further includes: data transfer and assist control logic means for controlling data transfer through the associated coupler unit, said latter means including means for producing appropriate interlock protocol signals to the respectively connected channel or control unit during said data transfer without having to transfer such protocol signals over the data link to the remote coupler unit.
Claim 8
Dependent Claim
25 words
A system as claimed in claim 6 and further including: means for correcting errors in data received at a coupler unit through the data link.
Claim 9
Dependent Claim
84 words
A system as claimed in claim 7 wherein the data error correcting means in each coupler unit includes: means for appending a correction code to data bytes to be transmitted to a remote coupler unit; means for locally generating a correction code to each data byte received at a coupler unit; means for comparing the locally-generated correction code with the appended correction code; and means for retransmitting the data from the remote coupler unit when said comparison means indicates an error in the data.
Claim 10
Independent Claim
34 words
A system as claimed in any one of the preceding claims and turther including: controller means for down loading operational programming to the coupler units to establish the desired personality of the coupler unit.
Claim 11
Dependent Claim
40 words
A system as claimed in claim 9 wherein the controller means is located in the vicinity of one site and downloads the operational programming of the coupler unit, that is located at the other remote site, through the data link.
Claim 12
Independent Claim
84 words
A system as claimed in any one of the preceding claims wherein the coupler unit connected to the channel includes: means for storing operational data for respective I/O devices connected to the control unit; counter means responsive to the storing means for holding a count representative of the number of bytes for a fixed length I/0 device; and means responsive to the counter means for generating a signal representative of the transfer of said number of bytes from the channel to terminate the transfer.
Claim 13
Independent Claim
212 words
A method for enabling an IBM CPU channel located at one site to communicate at high channel speeds through a channel-connected coupler unit, a serial bidirectional high channel speed data link and a control-unit-connected coupler unit with a control unit located at another site for data transfer with an I/O device, comprising the steps of: initiating first local interlocked sequences of signals at channel speed between the channel and the coupler unit that is connected thereto to establish data communication between the channel and its connected coupler unit; during said initiating step sending selected vectors between the coupler units over the data link to initiate second local interlocked sequences of signals at channel speed between the control unit and the coupler unit that is connected thereto to establish data communication between the control unit and its connected coupler unit; sending data over the data link between the channel at one site and the control unit at the other site without signal interlock between the coupler units and in a manner that is transparent to software in the CPU; and completing said data communication with the generation of local interlocked end sequences of signals respectively between the channel and its connected coupler unit and between the control unit and its connected coupler unit.
Claim 14
Independent Claim
212 words
A method for enabling an IBM CPU channel located at one site to communicate at high channel speeds through a channel-connected coupler unit, a serial bidirectional high channel speed data link and a control-unit-connected coupler unit with a control unit located at another site for data transfer with an I/O device, comprising the steps of: initiating first local interlocked sequences of signals at channel speed between the channel and the coupler unit that is connected thereto to establish data communication between the channel and its connected coupler unit; during said initiating step sending selected vectors between the coupler units over the data link to initiate second local interlocked sequences of signals at channel speed between the control unit and the coupler unit that is connected thereto to establish data communication between the control unit and its connected coupler unit; sending data over the data link between the channel at one site and the control unit at the other site without signal interlock between the coupler units and in a manner that is transparent to software in the CPU; and completing said data communication with the generation of local interlocked end sequences of signals respectively between the channel and its connected coupler unit and between the control unit and its connected coupler unit.
Claim 15
Dependent Claim
61 words
A method as claimed in claim 12 and further including the steps of: storing,...in each coupler unit, an entire block of data bytes to be transferred in response to an initial selection sequence at one site; and retransmitting a said stored data block when a data byte error has been detected after transmission of the data block through said data link.
Claim 16
Dependent Claim
47 words
A method as claimed in claim 13 and further including the steps of: enabling the second local interlocked sequences when a said data block is received at the remote coupler unit without error; and transferring said data block to an I/O device connected to said control unit.
Claim 17
Dependent Claim
64 words
A metnod as claimed in any one of claims 12 to 13 and further including the steps of: storing a count, representative of a predetermined number of data bytes intended for a fixed-length I/O device, in the coupler unit that is connected to the channel; and causing a correct count of data bytes during data transfer from the channel to its connected coupler unit.
Claim 18
Dependent Claim
46 words
A method as claimed in claim 15 wherein the causing step includes the steps of: altering the stored count in response to the transfer of each data byte from the channel; and halting further data transfer from the channel when a predetermined count has been reached.
Claim 19
Dependent Claim
21 words
A method as claimed in claim 16 wherein the altering step-comprises: decrementing the count until it has reached said predetermined count.
Claim 20
Dependent Claim
107 words
A method as claimed in claim 12 and further including the steps of: storing a first count representative of the number of bytes arrived from the channel at the remote coupler unit; storing a second count representative of the number of data bytes requested by the channel-connected coupler unit; comparing the first and second counts and generating a command retry sequence between the channel and its connected coupler unit when the first and second counts are not the same; and inhibiting transfer of said data bytes to the remote coupler unit during the retry sequence when the data bytes are intended for a fixed length I/O device.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.