System and method for testing computer components in development environments

• US 5,794,013 A
• Filed: 10/28/1996
• Issued: 08/11/1998
• Est. Priority Date: 10/28/1996
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: McBrearty, Gerald Francis
• Primary Examiner(s): Teska, Kevin J.
• Assistant Examiner(s): Irshadullah, M.
• Application Number:
  US08/739,083
• Time in Patent Office: 652 Days
• Field of Search: 395/500, 395/701, 395/829, 395/294, 395/183.09, 707/526
• US Class Current: 703/27
• CPC Class Codes: G06F 11/261 by simulating additional hardware, e.g. fault simulation

Abstract

A device emulator for use in testing pre-release program code emulates and replaces a first storage device such as a SCSI CD ROM drive containing the program code on CD ROM with a second storage device such as a SCSI hard drive. The emulator receives SCSI commands from an SCSI bus from a target system intended for the first drive. Through use of an emulator library, the emulator effects reads from the second device as if they were from the first device, and places the result on the SCSI bus. Testing personnel are thereby enabled to test the code on the second device which essentially behaves as the first device without the necessity of awaiting production and distribution of CD ROMs containing the test program code.

Claims

1. A method for emulating a first device with a second device for use in testing test program code in a computer system having a predetermined bus protocol carrying corresponding commands between said system and said first and second devices, said first and second devices having corresponding differing respective first and second operating characteristics, said method comprising the steps of:

storing in said second device said test program code;

placing said commands on said bus for said first device in said bus protocol;

translating said commands to adapted commands for said second device comprising

invoking an emulation module; and

translating, with said emulation module, said commands corresponding to said bus protocol and said first operating characteristic to said second operating characteristic;

transmitting said adapted commands to said second device;

actuating said second device in response to said adapted commands;

storing an emulation library containing a plurality of said emulation modules, each corresponding to a different pair of said first and second operating characteristics;

specifying one of said emulation modules from said emulation library; and

detecting from said commands on said bus said first operating characteristic, wherein said specifying one of said emulation modules is in response to said detecting.

2. The method of claim 1 further including:

generating signals from said second device in response to said actuating;

translating said signals to adapted signals corresponding to said bus protocol and said first device;

transmitting said adapted signals to said system over said bus; and

reading said adapted signals by said system as signals generated from said first device.

3. The method of claim 2 wherein said first and second devices are storage devices.

4. The method of claim 3 wherein said first and second devices are a CD ROM drive and hard drive, respectively.

5. The method of claim 4 wherein said CD ROM drive and said hard drive are an SCSI drive and SCSI hard drive, wherein said bus protocol is an SCSI protocol, and wherein said first and said second operating characteristics are operating characteristics of said SCSI CD ROM drive and said SCSI hard drive, respectively.

6. An apparatus for emulating a first device with a second device for use in testing program code in a computer system having a predetermined bus protocol carrying corresponding commands between said system and said first and second devices, said first and second devices having corresponding differing respective first and second operating characteristics, said apparatus comprising:

means for storing in said second device said test program code;

means for placing said commands on said bus for said first device in said bus protocol;

means for translating said commands to adapter commands for said second device comprising

means for invoking an emulation module; and

means for translating, with said emulation module, said commands corresponding to said protocol and bus said first operating characteristic to said second operating characteristic;

means for transmitting said adapted commands to said second device;

means for actuating said second device in response to said adapted commands;

means for storing an emulation library containing a plurality of said emulation modules, each corresponding to a different pair of said first and second operating characteristics;

means for specifying one of said emulation modules from said emulation library; and

means for detecting from said commands on said bus said first operating characteristic wherein said specifying one of said emulation modules is in response to said detecting.

7. The apparatus of claim 6 further including:

means for generating signals from said second device in response to said actuating;

means for translating said signals to adapted signals corresponding to said bus protocol and said first device;

means for transmitting said adapted signals to said system over said bus; and

means for reading said adapted signals by said system as signals generated from said first device.

8. The apparatus of claim 7 wherein said first and second devices are storage devices.

9. The apparatus of claim 8 wherein said first and second devices are a CD ROM drive and hard drive, respectively.

10. The apparatus of claim 9 wherein said CD ROM drive and said hard drive are an SCSI drive and SCSI hard drive, wherein said bus protocol is an SCSI protocol, and wherein said first and said second operating characteristics are operating characteristics of said SCSI CD ROM drive and said SCSI hard drive, respectively.