Extended distance fiber optic interface

• US 5,602,667 A
• Filed: 09/13/1995
• Issued: 02/11/1997
• Est. Priority Date: 10/07/1992
• Status: Expired due to Term

• Current Assignee: Unisys Corporation
• Original Assignee: Unisys Corporation
• Inventors: Patel, Narottam N.
• Primary Examiner(s): PASCAL, LESLIE C
• Application Number:
  US08/527,743
• Time in Patent Office: 517 Days
• Field of Search: 359/135-138, 359/140, 359/158, 359/159, 359/161, 359/173
• US Class Current: 398/141
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices

Abstract

A device controller for coupling various peripheral devices to a host computer while compensating for distances of up to 10 kilometers. The basic interface medium is fiber optics. The chosen protocol may be functionally equivalent to an existing electrical interface standard or may comply with an interface standard designed specifically for fiber optic input/output communication. The time delays associated with distances of from 500 feet to 10 kilometers are automatically provided by manually switching to the maximum distance mode. An embedded RISC provides the basic logic for the device controller. Further efficiencies are provided by permitting Futurebus+ and disk storage subsystem data exchanges without involvement by the host computer.

Claims

1. An apparatus comprising:

a. a host computer, at least a portion of said host computer operating in accordance with a first predetermined parallel electrical communication protocol;

b. a peripheral device, at least a portion of said peripheral device operating in accordance with a second predetermined parallel electrical communication protocol;

c. a device controller coupled to said portion of said peripheral device that operates in accordance with said second predetermined parallel electrical communication protocol via a cable and wherein said device controller is located at a variable distance from said host computer of up to 10 kilometers;

d. a fiber optic input/output link coupled to said portion of said host computer that operates in accordance with said first predetermined parallel electrical communication protocol and further coupled to said device controller, said fiber optic input/output link having a length that substantially matches said variable distance from said host computer to said device controller and operates in accordance with a predetermined serial optical communication protocol;

e. first interfacing means coupled to said host computer and further coupled to said fiber optic input/output link for interfacing between said first predetermined parallel electrical communication protocol and said serial optical communication protocol;

f. second interfacing means coupled to said device controller and further coupled to said fiber optic input/output link for interfacing between said second predetermined parallel electrical communication protocol and said serial optical communication protocol; and

g. at least one of said first and second interfacing means further including means for accommodating said variable distance such that said operation of said host computer is independent of said variable distance, said means for accommodating including a buffering means.

2. An apparatus according to claim 1 wherein said first predetermined parallel electrical communication protocol is compatible with an existing electrical interface.

3. An apparatus according to claim 2 wherein said existing electrical interface comprises the Block Multiplexer Channel protocol.

4. An apparatus according to claim 2 wherein said existing electrical interface comprises the ESCON protocol.

5. An apparatus according to claim 1 or 2 or 3 or 4 wherein said device controller further comprises:

a. an additional interface which may be coupled to an additional peripheral device via an additional cable.

6. An apparatus according to claim 5 wherein said additional interface is compatible with Futurebus+.

7. An apparatus according to claim 6 wherein said device controller further comprises an embedded Reduced Instruction Set Computer.

8. An apparatus according to claim 7 wherein said device controller further comprises a disk storage subsystem.

9. An apparatus according to claim 8 wherein said device controller further comprises:

a. means for transferring data directly between said disk storage subsystem and said Futurebus+ interface.

10. An apparatus according to claim 1 wherein said second predetermined parallel electrical communication protocol is compatible with an existing electrical interface.

11. An apparatus according to claim 10 wherein said existing electrical interface comprises the Block Multiplexer Channel protocol.

12. An apparatus according to claim 10 wherein said existing electrical interface comprises the ESCON protocol.

13. An apparatus for transferring data between a host computer having a Block Multiplexer Channel interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a device controller having a communication interface which is compatible with the Block Multiplexer Channel interface and further having a plurality of peripheral device interfaces coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

b. a fiber optic medium coupling the host computer Block Multiplexer Channel interface to the device controller communication interface; and

c. a memory device located within said device controller for buffering the transferred data to the plurality of peripheral devices.

22. An apparatus according to claims 13, 14, 15, 16, 17, 18, 19, 20 or 21 where said memory device is contained within a Reduced Instruction Set Computer.

14. An apparatus for transferring data between a host computer having an electrical interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a device controller having a Block Multiplexer Channel interface which is compatible with the electrical interface and further having a plurality of peripheral device interfaces coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

b. a fiber optic medium coupling the host computer electrical interface to the device controller Block Multiplexer Channel interface; and

c. a memory device located within said device controller for buffering the transferred data to the plurality of peripheral devices.

15. An apparatus for transferring data between a host computer having an ESCON interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a device controller having a communication interface which is compatible with the ESCON interface and further having a plurality of peripheral device interfaces coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

b. a fiber optic medium coupling the host computer ESCON interface to the device controller communication interface; and

c. a memory device located within said device controller for buffering the transferred data to the plurality of peripheral devices.

16. An apparatus for transferring data between a host computer having an electrical interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a device controller having an ESCON interface which is compatible with the electrical interface and further having a plurality of peripheral device interfaces coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

b. a fiber optic medium coupling the host computer electrical interface to the device controller ESCON interface; and

c. a memory device located within said device controller for buffering the transferred data to the plurality of peripheral devices.

17. An apparatus for transferring data between a host computer having an electrical interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a device controller having a communication interface which is compatible with the electrical interface, at least one of a plurality of peripheral device interfaces coupled to at least one of the plurality of peripheral devices via at least one of the plurality of peripheral device interfaces, at least another of the plurality of peripheral device interfaces coupled to at least another of the plurality of peripheral devices via at least one of a plurality of FUTUREBUS+ interfaces;

b. a fiber optic medium coupling the host computer electrical interface to the device controller communication interface; and

c. a memory device located within said device controller for buffering the transferred data to the host computer.

18. An apparatus for transferring data between a host computer having a Block Multiplexer Channel interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a device controller having a communication interface which is compatible with the Block Multiplexer Channel interface and further having a plurality of peripheral device interfaces coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

b. a fiber optic medium coupling the host computer Block Multiplexer Channel interface to the device controller communication interface; and

c. a memory device located within said device controller for buffering the transferred data to the host computer.

19. An apparatus for transferring data between a host computer having an electrical interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a device controller having a Block Multiplexer Channel interface which is compatible with the electrical interface and further having a plurality of peripheral device interfaces coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

b. a fiber optic medium coupling the host computer electrical interface to the device controller Block Multiplexer Channel interface; and

c. a memory device located within said device controller for buffering the transferred data to the host computer.

20. An apparatus for transferring data between a host computer having an ESCON interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a device controller having a communication interface which is compatible with the ESCON interface and further having a plurality of peripheral device interfaces coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

b. a fiber optic medium coupling the host computer ESCON interface to the device controller communication interface; and

c. a memory device located within said device controller for buffering the transferred data to the host computer.

21. An apparatus for transferring data between a host computer having an electrical interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a device controller having an ESCON interface which is compatible with the electrical interface and further having a plurality of peripheral device interfaces coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

b. a fiber optic medium coupling the host computer electrical interface to the device controller ESCON interface; and

c. a memory device located within said device controller for buffering the transferred data to the host computer.

23. An apparatus for transferring data between a host computer having an electrical interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a host converter having a fiber optic interface, the host converter is coupled to the electrical interface of the host computer and converts the data from an electrical representation to an optical representation;

b. a device controller having a plurality of peripheral device interfaces, the device controller is coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

c. a controller converter having a fiber optic interface, the controller converter is coupled to the device controller and converts the data from an optical representation to an electrical representation;

d. a controller memory device coupled to the controller converter and further coupled to the plurality of peripheral device interfaces for buffering the transferred data to the peripheral devices;

e. a fiber optic medium coupling the fiber optic interface of the host converter to the fiber optic interface of the controller converter; and

f. a protocol controller coupled to the controller converter and further coupled to the controller memory device for controlling the protocol used during the data transfer.

24. An apparatus according to claim 23 wherein the protocol controller provides a FIFPS60 protocol.

25. An apparatus according to claim 23 wherein the protocol controller provides a modified FIFPS60 protocol.

26. An apparatus for transferring data between a host computer having an electrical interface and a plurality of peripheral devices located at a distance of up to 10 kilometers therefrom comprising:

a. a host converter having a fiber optic interface, the host converter is coupled to the electrical interface of the host computer and converts the data from an optical representation to an electrical representation;

b. a device controller having a plurality of peripheral device interfaces, the device controller is coupled to the plurality of peripheral devices via the plurality of peripheral device interfaces;

c. a controller converter having a fiber optic interface, the controller converter is coupled to the device controller and converts the data from an electrical representation to an optical representation;

d. a controller memory device coupled to the controller converter and further coupled to the plurality of peripheral device interfaces for buffering the transferred data from the peripheral devices;

e. a fiber optic medium coupling the fiber optic interface of the host converter to the fiber optic interface of the controller converter; and

f. a protocol controller coupled to the controller converter and further coupled to the controller memory device for controlling the protocol used during the data transfer.

27. An apparatus according to claim 26 wherein the protocol controller provides a FIFPS60 protocol.

28. An apparatus according to claim 26 wherein the protocol controller provides a modified FIFPS60 protocol.