Browse Prior Art Database

Two External Interrupts for the 8031 Microprocessor Family

IP.com Disclosure Number: IPCOM000123883D
Original Publication Date: 1999-Jun-01
Included in the Prior Art Database: 2005-Apr-05
Document File: 2 page(s) / 40K

Publishing Venue

IBM

Related People

Benayoun, A: AUTHOR [+4]

Abstract

The problem to fix is how to have more than 2 external interrupts on the 8031 microprocessor family.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Two External Interrupts for the 8031 Microprocessor Family

   Problem Description

   The problem to fix is how to have more than 2 external
interrupts on the 8031 microprocessor family.

   State of the Art

   The particularity of the 8031 micro controllers is :
  o  Two external interrupts
  o  Two external programmable counters
  o  One serial  programmable port

   It is not very seldom when more than two external
interrupts are needed in a micro controller based design or
subsystem.

   Applications of the Invention

   The problem occurs when more than two interrupts are
needed, in this case, an extra device is needed: an interrupt
controller, this solution is more expensive and needs a lot of
additional room on the card.

   Description of the Invention

   The major idea is to use the external timers: T1 and T2 as
external interrupts: The programmer has to program the internal
double registers: TL1 and TH1 for the timer 1 and TL2 and TH2 for
the timer 2 with the 'F F'H value.

   When the next external transition occurs on timer 1 for
example, TL1 and TH1 overflows and goes to '00'H, and an internal
interrupt is generated so that the micro controller knows the origin
of this artificial but efficient interrupt.