Robert W Woods

US Patent:

62633953, Jul 17, 2001

Filed:

Jan 6, 1999

Appl. No.:

9/227510

Inventors:

Patrick L. Ferguson - Cypress TX
Paul B. Rawlins - Spring TX
David F. Heinrich - Tomball TX
Robert L. Woods - Allentown PA

Assignee:

Compaq Computer Corp. - Houston TX

International Classification:

C06F 1314
C06F 948

US Classification:

710262

Abstract:

An interrupt controller may serially scan a plurality of interrupt request signals and/or receive interrupt request signals on parallel inputs. A scan latency may be associated with updating the status of serially scanned interrupt requests. Spurious interrupts may result from the scan latency. To reduce the chance of spurious interrupts, serially scanned interrupt requests may be masked for an amount of time following an end of interrupt (EOI). Write cycles to clear interrupt requests may be posted in a write buffer. The delay of such write cycles clearing the write buffer may also result in spurious interrupts. To reduce the chance of such spurious interrupts, EOI cycles may be delayed or retried until the write buffer empties.