Method and apparatus for transferring data from SCSI bus to serial device and from serial device to SCSI bus

• US 5,748,924 A
• Filed: 10/17/1995
• Issued: 05/05/1998
• Est. Priority Date: 10/17/1995
• Status: Expired due to Fees

• Current Assignee: Methode Electronics Incorporated
• Original Assignee: Methode Electronics Incorporated
• Inventors: Wang, Huili, Llorens, Joseph R.
• Primary Examiner(s): Harvey, Jack B.
• Assistant Examiner(s): DHARIA, RUPAL
• Application Number:
  US08/544,275
• Time in Patent Office: 931 Days
• Field of Search: 395/891, 395/309, 395/200.21, 395/200.01, 395/892, 395/885, 341/100, 341/101
• US Class Current: 710/62
• CPC Class Codes: G06F 13/4045 where the bus bridge performs an extender function

Abstract

An adapter for performing bi-directional data transfers between a SCSI bus, which transfers data using a parallel format, and a serial transfer medium, which transfers data using a serial format and being connected to a serial device. The adapter bi-directionally transfers SCSI data between itself and the SCSI bus. In addition, the adapter bi-directionally converts between SCSI formatted data and serially formatted data. Furthermore, the adapter bi-directionally transfers serially formatted data between itself and the serial transfer medium.

Claims

1. An adapter for performing bi-directional data transfers between a SCSI bus, and a serial transfer medium, said adapter comprising:

a) a SCSI controller providing bi-directional parallel SCSI data transfers between said SCSI bus and said adapter according to standard SCSI protocol;

b) a serial port providing bi-directional serial format data transfers between said adapter and said serial transfer medium;

c) a micro-controller for converting SCSI data received by said SCSI controller to serial format data to be transferred to said serial transfer medium through said serial port, and for converting serial data received by said serial port to parallel SCSI data to be transferred to said SCSI bus through said SCSI controller; and

d) a memory device for temporarily storing SCSI data received by said SCSI controller to be converted to serial data, and SCSI data having been converted from serial data received by said serial port to be transferred to said SCSI bus.

2. The adapter of claim 1, wherein said memory device comprises an eight bit first in first out memory device such that eight bit data words stored in said memory device will be read from said memory device in the order in which they are stored.

3. The adapter of claim 2, further comprising means for storing programmed instructions for controlling said micro-controller connected to said micro-controller.

4. The adapter of claim 3 wherein said serial transfer medium consists of a transmission line.

5. The adapter of claim 3, wherein said serial transfer medium consists of an optical fiber.

6. The adapter of claim 3, wherein said serial transfer medium consists of a wireless transfer means.

7. The adapter of claim 3 wherein said serial data conforms to the RS-232 standard.

8. The adapter of claim 3 wherein said serial data conforms to the RS-488 standard.

9. The adapter of claim 3 wherein said serial data conforms to the Fiber Channel standard.

10. An adapter for performing bi-directional data transfers between a SCSI bus and a serial device, said adapter comprising:

a micro-controller for converting parallel format SCSI data signals to serial format data signals, and for converting serial format data signals to parallel format SCSI signals;

a SCSI controller electrically disposed between said SCSI bus and said micro-controller, for controlling bi-directional parallel SCSI data exchange between said SCSI bus and said micro-controller;

a serial port for controlling bi-directional serial data exchange between said serial device and said micro controller;

whereby

said micro-controller receives parallel SCSI signals from said SCSI controller, converts said SCSI signals to a serial data format, and outputs said converted serial data signals to said serial port; and

said micro-controller receives serial format data signals from said serial port, converts said serial data signals to parallel SCSI format signals, and outputs said converted SCSI signals to said SCSI controller.

11. The adapter of claim 10, further comprising a memory device connected to said micro-controller, said micro-controller temporarily storing within said memory device both parallel data received from said SCSI controller prior to converting said parallel data to serial data, and said parallel data converted by said micro-controller from serial data received from said serial port prior to be output to said SCSI controller.

12. The adapter of claim 11 wherein said memory device consists of a FIFO memory wherein said parallel data stored in said FIFO memory is read from said FIFO memory in the same order said data was written thereto.

13. The adapter of claim 12 further comprising a program memory connected to said micro-controller.

14. The adapter of claim 13 wherein said serial device consists of a modem.

15. A method of bi-directionally transferring data between a parallel format SCSI bus and a serial device, said method comprising the steps of:

transferring data from said SCSI bus to said serial device; and

transferring data from said serial device to said SCSI bus;

wherein the step of transferring data from said SCSI bus to said serial device further comprises the steps of;

receiving parallel format data words from said SCSI bus;

sequentially storing the parallel data words received from said SCSI bus in a memory device in the order in which they are received;

sequentially converting the parallel data words stored in said memory device into serial format data, the parallel words being converted in the order in which they are stored in said memory device;

transmitting the serial formatted data to said serial device; and

wherein the step of transferring data from said SCSI bus to said serial device further comprises the steps of;

receiving serial formatted data from said serial device;

converting the serial format data received from said serial device into parallel format data words;

sequentially storing the converted parallel format data words in said memory device;

sequentially writing the converted parallel format data words stored in said memory device to said SCSI bus in the order in which they are stored within said memory device.

16. The method of claim 15, wherein said memory device is a FIFO memory such that parallel data words read into the memory are written out of the memory in the same order as which the are written.