Honeywell Information Systems Inc.

Richard C Zelley

Edward R Salas

Daniel A Boudreau

A single computer board data processing system includes a multiport memory system which is accessible by I/O controllers through a system bus I/O memory port or directly by the system's central processing unit (CPU) via a CPU memory port. The logic and control circuits of the memory ports and CPU are included within the computer main board while memory modules/pacs are contained on one or more memory daughter boards which plug into memory input/output connectors contained on the main board. The port address and data paths connect in common to the memory connectors for transmitting and receiving memory addresses and data between the memory modules and the CPU and I/O ports. At least one register connects between the CPU and to common address path. When the CPU is placed in a diagnostic mode of operation, this register together with existing data registers are conditioned to store signals representative of the address and data being transmitted to the memory modules enabling the CPU to diagnose whether the main board or portions thereof has failed without requiring any testing of the memory modules.

Growing community of inventors

Billerica, MA, United States of America

Richard C Zelley