Design methodology and microdiagnostics development for a self-checking microprocessor

ABSTRACT

The conventional design of electronic circuits is intolerant to operational faults. Self-checking logic is aimed at online fault detection and can hence be incorporated to achieve reliable operation. In this paper, the design of a self-checking microprocessor is discussed. Self-checking strategies for different functional units are selectively and judiciously applied, and also modified wherever necessary, for the design of the register section, the arithmetic & logic unit and the control unit. A self-checking microprogrammed control unit, capable of supporting normal instruction execution concurrently with diagnostics, is developed. The design methodology has been applied to Intel's 8085A microprocessor as a case study to make it self-testing. Overheads involved have also been estimated.

REFERENCES

• 1: D.A. Rennels, ' Fault. Toterant Computing - Concepts b Examples', IEEE Trans. Computers, Vol. C-33, No. 12, Oecember 1984, PP. 1116-1129.
• 2: Parag K. Lala, Fault tolerant and fault testable hardware design, Prentice-Hall, Inc., Upper Saddle River, NJ, 1985
• 3: S.M. Thatte b J.A. Abraham, 'Test Generation for Microprocessors ' , IEEE Trans. Computer, Vol. c-29, No. 6, June 1980. pp. 430-441.
• 4: George D. Kraft , Wing N. Toy, Microprogrammed Control and Reliable Design of Small Computers, Prentice Hall Professional Technical Reference, 1981
• 5: M.P. lialbert b S.M. Bose, 'Design approach for a VLSI Self-Checking MIL-.STO-.1750A Microprocessor', Proc. 14th Int. Symp. on Fault-Tolerant Computing, IEEE-CS Press, June 1984, pp. 254-253.
• 6: F. Somenzi t G. Silvano. 'Fault Detection in Programmable Logic Arrays', Proc. IEEE, Vol. 74. No. 5, May 1986, pp. 655-668.
• 7: M. Nicolaidis, 'Evaluation of a Self-Checking Version of the MC68000 Microprocessor', Proc. 15th Int. Symp. on Fault-Toterant Computing, IEEE- CS Press, June 1985, pp. 350-356.
• 8: Y. Crouzet ~ C. Landrault, 'Design of Self-Checking MOS-LSI Circuits: application to a Four.- Bit Microprocessor', IEEE Trans. Computers, Vol. C-23, No. 6, June 1980, pp. 532-537.
• 9: R.W. Goody, THE INTELLIGENT MICROCOMPUTER, Science Research Associates, Inc., 1982.
• 10: R.A. Parekhji, 'Design Methodology for a Self-Checking Microprocessor', M. Tech. Dissertation, University Of Roorkee, Roorkee, India, February 1988.
• 11: T. Nanya b T. Kawamura, ' Error Secure/Propagating Concept and Its Application to the Design of Strongly Fault-Secure Processors, Proc. 15th Int. Symp. on Fault-toterant Computing, IEEE-CS Press, June 1985, pp. 396-401.

INDEX TERMS

Primary Classification:
  B. Hardware
  B.1 CONTROL STRUCTURES AND MICROPROGRAMMING
      B.1.5 Microcode Applications
          Subjects: Instruction set interpretation

Additional Classification:
  B. Hardware
  B.1 CONTROL STRUCTURES AND MICROPROGRAMMING
      B.1.3 Control Structure Reliability, Testing, and Fault-Tolerance**
          Subjects: Error-checking**
  B.2 ARITHMETIC AND LOGIC STRUCTURES
      B.2.1 Design Styles
          Subjects: Parallel

  C. Computer Systems Organization
  C.5 COMPUTER SYSTEM IMPLEMENTATION
      C.5.3 Microcomputers

          Nouns: Zilog Z8000

General Terms:
Algorithms, Design, Performance, Reliability, Verification