Method and apparatus for interfacing between peripherals of multiple formats and a single system bus

• US 5,905,885 A
• Filed: 09/19/1997
• Issued: 05/18/1999
• Est. Priority Date: 06/27/1994
• Status: Expired due to Term

• Current Assignee: Cirrus Logic Incorporated
• Original Assignee: Cirrus Logic Incorporated
• Inventors: Vaidyanathan, Arunachalam, Shetty, Suhas Anand, Gopalaswamy, Kasturiraman, Smith, Stephen A., Bezzant, Daniel G., Richter, Bryan M.
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): FREJD, RUSSELL WARREN
• Application Number:
  US08/933,884
• Time in Patent Office: 606 Days
• Field of Search: 395/500, 395/828, 395/882, 395/884, 395/831, 395/823, 395/825, 395/835, 395/832, 395/883
• US Class Current: 710/5
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices

Abstract

A peripheral interface system and apparatus including a pair of integrated circuits, referred to as a system adapter and a socket controller, use a communication protocol, referred to as a windowed-interchip-communication protocol, to interface peripherals, such as PCMCIA cards or infrared devices, and other subsystems having different formats with a CPU system bus. The system adapter communicates to a hard disk drive subsystem using the ATA communication standards to interface an ATA hard disk drive with the CPU system bus. Communication between the system adapter and the socket controller, which communicates with PCMCIA peripheral cards and IR peripherals, is accomplished using the windowed-interchip-communication protocol which may share hardware resources with other communication protocols. Communication between the system adapter and the hard disk drive and between the system adapter and the socket controller may be provided on the same chain of a standard 40 signal ribbon cable. Alternatively communication between an expansion board and a socket controller may be performed across a cable separate from the hard disk drives having a different signal line format. The system adapter may be included within a single interface expansion board which can be connected to the motherboard and CPU system bus or it can be directly connected or soldered to the motherboard and communicate with the socket controller and ATA hard disk drives using one or more busses.

Claims

1. A communications integrated circuit for controlling bidirectional communication between a central processing unit (CPU) and a socket controller, the communications integrated circuit comprising:

a system bus interface circuit coupled to the CPU according to a predetermined system bus configuration for bidirectional communication between the system bus interface circuit and the CPU using a system bus communication protocol;

a socket controller interface circuit selectively coupled to the socket controller according to a predetermined communications bus configuration for bidirectional communication between the socket controller interface circuit and the socket controller using a selectable communication protocol;

a storage means coupled to the system bus interface circuit and the socket controller interface circuit for receiving control data and storing status information; and

a control circuit coupled to the system bus interface circuit, the socket controller interface circuit, and the storage means, for controlling the bidirectional communication between the system bus interface circuit and the CPU, for controlling the bidirectional communication between the socket controller interface and the controller, and for translating control and command data between the system bus protocol and the selectable communication protocol.

2. A socket controller integrated circuit coupled to a communications integrated circuit and a peripheral for controlling communication between the communications integrated circuit and the peripheral, the controller integrated circuit comprising:

a communications interface circuit coupled to a communications integrated circuit according to a predetermined communications bus configuration for bidirectional communication using a selectable communication protocol;

a peripheral controller interface circuit coupled to a peripheral according to a predetermined peripheral bus configuration for communication using a predetermined peripheral protocol;

a storage means coupled to the communications interface circuit and the peripheral controller interface circuit for receiving control data and storing status information; and

a control circuit coupled to the communications interface circuit, the peripheral controller interface circuit, and the storage means, for controlling bidirectional communication between the communications interface circuit and the communications integrated circuit and for controlling the bidirectional communications between the peripheral controller circuit and the peripheral, and for translating control and command data between the peripheral protocol and the selectable communication protocol.

3. The controller integrated circuit as claimed in claim 2 further comprising an infrared controller circuit coupled to the control circuit and the storage means, and configurable for coupling to an infrared transceiver, for controlling the bidirectional communication to an infrared transceiver and for controlling the bidirectional communication between the bus interface circuit and the communications integrated circuit.

4. The controller integrated circuit as claimed in claim 3 wherein the communications integrated circuit is a system adapter.

5. A socket controller integrated circuit coupled to a communications integrated circuit and a peripheral for controlling communication between a communications integrated circuit, an array of system memory, and a peripheral, the socket controller integrated circuit comprising:

a communications interface circuit selectively coupled to the communications integrated circuit according to a predetermined communications bus configuration for bidirectional communication using a selected communication protocol;

a peripheral controller interface circuit selectively coupled to the peripheral according to a predetermined peripheral bus configuration for bidirectional communication;

a storage means coupled to the communications interface circuit and the peripheral controller circuit for receiving control data and storing status information; and

a control circuit coupled to the communications interface circuit, the peripheral controller circuit, and the storage means, for communication to the communications integrated circuit, the array of system memory, and the peripheral, the control circuit comprising a direct memory access control circuit coupled to the peripheral controller circuit for controlling the bidirectional communications between the communications interface circuit, the communications integrated circuit, and to the array of system memory and for controlling the bidirectional communication between the peripheral controller circuit and the peripheral.

6. The controller integrated circuit as claimed in claim 5 wherein the peripheral is a PCMCIA peripheral.

7. The controller integrated circuit as claimed in claim 6 wherein the communications integrated circuit is a system adapter.

8. A method of controlling bidirectional communication for reducing an access time for a long read operation over an interface between a system adapter coupled to a socket controller, the socket controller coupled to and communicating with a plurality of peripherals, the socket controller, the method of bidirectional communication for simultaneously communicating a first data from the system adapter to the socket controller over the interface and a second data from the socket controller to the system adapter over the interface during a first cycle if a read operation is executed over the interface, wherein the interface comprises a data bus coupled to the system adapter and the socket controller, a predetermined select signal having an active state and an inactive state, a predetermined read signal having an active state and an inactive state, and a predetermined service request signal for requesting service having an active state and an inactive state, the method comprising the steps of:

a) holding the predetermined select signal in an inactive state to inhibit bidirectional communication;

b) activating the predetermined read signal during the first cycle to enable bidirectional communication if a read operation is executed over the interface;

c) activating the predetermined read signal during a second cycle to enable bidirectional communication if a read operation is executed over the interface;

d) activating the predetermined read signal during a third cycle to enable bidirectional communication if a read operation is executed over the interface;

e) activating the predetermined write signal during the first cycle to enable bidirectional communication if a write operation is executed over the interface;

f) activating the predetermined write signal during the second cycle to enable bidirectional communication if a write operation is executed over the interface;

g) holding both the predetermined read signal and the predetermined write signal in an inactive state during the first cycle to inhibit bidirectional communication if no operation is executed over the interface;

h) monitoring the predetermined service request signal;

i) activating the predetermined read signal to determine if one of the plurality of peripherals is requesting service if the predetermined service request signal is active;

j) determining if the predetermined service request signal is still active; and

K) repeating steps h through j for each successive one of the plurality of peripherals until the predetermined service request signal is inactive.

9. The method of bidirectional communication over the interface as claimed in claim 8 wherein the first data is communicated from the system adapter to the socket controller and the second data is simultaneously communicated from the socket controller to the system adapter over the data bus of the interface upon the activation of the read signal.

10. The method of bidirectional communication over the interface as claimed in claim 9 wherein the interface is an ATA interface.

11. A method of controlling bidirectional communication for reducing information transfer and signal activity over an interface between a system adapter coupled to a socket controller, the socket controller coupled to a plurality of sockets and a peripheral, the method comprising the steps of:

specifying a plurality of storage locations coupled to the system adapter, the socket controller, the plurality of sockets and the peripheral for information to be transferred to and from the system adapter, the socket controller, the plurality of sockets and the peripheral;

pointing to a storage location within the specified plurality of storage locations coupled to the system adapter, the socket controller, the plurality of sockets and the peripheral for information to be transferred to from the system adapter, the socket controller, the plurality of sockets and the peripheral; and

selecting one of the plurality of sockets and the peripheral from which to transfer information to one of the plurality of storage locations pointed to,

wherein the plurality of storage locations is specified by a window number, the selected one of the plurality of sockets and the peripheral is selected by a socket number, and the specified plurality of storage locations is pointed to by a storage location address.

12. The method of bidirectional communication as in claim 11 further comprising the step of:

selecting a communication operation.

13. A method of controlling bidirectional communication for reducing information transfer and signal activity over an interface between a system adapter coupled to a socket controller, the socket controller coupled to a plurality of sockets and a peripheral, the method comprising the steps of:

specifying a plurality of storage locations coupled to the system adapter, the socket controller, the plurality of sockets and the peripheral for information to be transferred to and from the system adapter, the socket controller, the plurality of sockets and the peripheral;

pointing to a storage location within the specified plurality of storage locations coupled to the system adapter, the socket controller, the plurality of sockets and the peripheral for information to be transferred to from the system adapter, the socket controller, the plurality of sockets and the peripheral;

selecting one of the plurality of sockets and the peripheral from which to transfer information to one of the plurality of storage locations pointed to; and

selecting a communication operation,

wherein the plurality of storage locations is specified by a window number, the selected one of the plurality of sockets and the peripheral is selected by a socket number, the specified plurality of storage locations is pointed to by a storage location address, and the communications operation is selected by an op code.

14. A bidirectional communication apparatus for reducing information transfer and signal activity on an interface between a system adapter and a socket controller, the socket controller coupled to a plurality of sockets and a peripheral, the bidirectional communication apparatus comprising:

a signal path coupled between the system adapter and the socket controller for conducting bidirectional communication;

a first means for communicating in one of two directions, between the system adapter and the socket controller via the signal path, a first address specifying a plurality of storage locations;

a second means for communicating in one of two directions, between the system adapter and the socket controller via the signal path, a second address for selecting one of a plurality of sockets;

a third means for communicating, in one of two directions, between the system adapter and the socket controller via the signal path, a third address for pointing to a storage location within the specified plurality of storage locations; and

a fourth means for communicating, between the system adapter and the socket controller via the signal path, a fourth for selecting a communication operation,

wherein the first address is a window number, the second address is a socket number, the third address is a storage location, and the fourth address is an op code.

15. A system for controlling communications between a central processing unit (CPU) and a peripheral, comprising:

a communications integrated circuit for controlling bidirectional communication between the CPU and a socket controller, the communications integrated circuit comprising;

a system bus interface circuit coupled to the CPU according to a predetermined system bus configuration for bidirectional communication between the system bus interface circuit and the CPU using a system bus communication protocol;

a socket controller interface circuit selectively coupled to the socket controller according to a predetermined communications bus configuration for bidirectional communication between the socket controller interface circuit and the socket controller using a selectable communication protocol;

a first storage means coupled to the system bus interface circuit and the socket controller interface circuit for receiving control data and storing status information; and

a control circuit coupled to the system bus interface circuit, the socket controller interface circuit, and the first storage means, for controlling the bidirectional communication between the system bus interface circuit and the CPU, for controlling the bidirectional communication between the socket controller interface and the controller, and for translating control and command data between the system bus protocol and the selectable communication protocol, and

a socket controller integrated circuit coupled to the communications integrated circuit and a peripheral for controlling communication between the communications integrated circuit and the peripheral, the controller integrated circuit comprising;

a communications interface circuit coupled to a communications integrated circuit according to a predetermined communications bus configuration for bidirectional communication using a selectable communication protocol;

a peripheral controller interface circuit coupled to a peripheral according to a predetermined peripheral bus configuration for communication using a predetermined peripheral protocol;

a second storage means coupled to the communications interface circuit and the peripheral controller interface circuit for receiving control data and storing status information; and

a control circuit coupled to the communications interface circuit, the peripheral controller interface circuit, and the second storage means, for controlling bidirectional communication between the communications interface circuit and the communications integrated circuit and for controlling the bidirectional communications between the peripheral controller circuit and the peripheral, and for translating control and command data between the peripheral protocol and the selectable communication protocol.