Withdrawn Standard. Withdrawn Date: Jan 15, 2001. No longer endorsed by the IEEE. An 8-bit microcomputer bus system derived from the industry bus known as the STD bus is described. The STD bus is a modular packaging and interconnect scheme for 8-bit microprocessor card systems. The bus size and bus organization were selected to serve the interface between any 8-bit microprocessor and a variety of memory and I/O functions. Logical, timing, electrical, and mechanical specifications are provided. The body of the standard provides a core specification for the device-independent parameters. Appendixes provide device-dependent parameters for various processors. This document also contains ANSI/IEEE Std 1101-1987, IEEE Standard for Mechanical Core Specifications for Microcomputers.