Diagnostic Status for Non-Maskable Interrupt Arbitration
Original Publication Date: 1987-Oct-01
Included in the Prior Art Database: 2005-Feb-02
A technique is described whereby a diagnostic status port is provided by the central arbiter for computers using non-maskable interrupt (NMI) arbitration. The concept enables the computer to perform error recovery when an NMI occurs. It allows diagnostics to be performed or enables the operating system program to disconnect a connected device and to advise the user that the device is no longer functioning. (Image Omitted) The NMI subroutine incorporating the diagnostic function is shown in the dotted section of the flow chart. When an NMI is detected, the central arbiter provides status in a port to allow the central processing unit (CPU) to determine the type of error, enabling the CPU to read whether the NMI has occurred due to a bus time-out.