Method for evaluating signals with the aid of a timer and an overrun counter

US6625571B1 · kind B1 · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Harald Michi · Heilbronn, DE
• Bernd Lichtenberg · Bietigheim-Bissingen, DE
• Michael Rink · Gerlingen, DE
• Werner Uhler · Bruchsal, DE

Key dates

• Filing date: Aug 6, 2001
• Grant date: Sep 23, 2003
• Expiry date: Aug 6, 2021

Classification

• Technology area (CPC G): Physics
• CPC primary: G01P3/489
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for signal evaluation, e.g. with pulse wheels, is described, in which the distance between predeterminable signal edges is determined in a microcontroller that has a CPU, timer, and memory, in that upon the occurrence of signal edges, an interrupt is triggered with which the existing timer values are stored. Based on the difference between predeterminable timer values, time intervals are determined which are inversely proportional to the velocity or speed. So that it is possible to use timers with a relatively low bit count, for example 16 bits, the numerical values obtained when there is a timer overflow are also determined and are taken into account in the determination of the distances. If drum stores are used, only four bits per drum store value are required, one check bit and three bits as an overflow counter.